9+ Development Theories (Definitions + Examples)

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Have you ever wondered why babies love peek-a-boo or why teenagers often feel like they're stuck between being kids and adults? That's because all of us go through different stages as we grow up.

Development theories are like maps that help us understand the stages of growth. They tell us about the changes we can expect in our feelings, thoughts, and behaviors as we get older.

By understanding these theories, we can better appreciate why people act the way they do at different ages. In this article, we'll explore some of the most famous maps or theories that explain how we grow and change throughout our lives.

How Did Development Theories Start?

Long ago, people looked at children's growth and behavior mostly based on traditions and beliefs. They didn't have fancy tools or methods to study these things. But as centuries went by, things began to change.

- Ancient Times: People like the Greeks, including philosophers like Plato and Aristotle, had their own ideas about children and learning. Plato believed in innate knowledge, meaning he thought kids were born with some knowledge. Aristotle, on the other hand, believed kids learned from their experiences.

- 17th Century: A guy named John Locke came around. He thought of the child's mind as a "blank slate," also known as "tabula rasa," meaning kids are born knowing nothing and learn everything from experiences. His ideas influenced many others.

baby in a crib

- Late 1800s: Now, we get to a period where people started taking a scientific approach. A man named G. Stanley Hall is often called the "father of child psychology" in America. He believed that children's development happened in stages, much like how animals evolve.

- Early 1900s: This was an exciting time! Sigmund Freud introduced his theory that kids go through different stages focused on various parts of their body, like the mouth or hands. While some of his ideas seem a bit strange today, they were groundbreaking back then.

- Mid-1900s: More thinkers emerged. Jean Piaget talked about how kids think and learn in stages. Erik Erikson discussed the emotional and social challenges people face at different ages.

With each of these milestones, our understanding of how humans grow and change got better. These early thinkers were like trailblazers in a vast forest, making paths for others to follow. Today, we continue to build on their ideas, making our "maps" of human development clearer and more detailed.

1) Freud's Psychosexual Stages Theory

In the early 1900s, there was a man named Sigmund Freud from Austria. He had some pretty unique ideas about how kids grow up. He believed that as we grow, we go through different stages focused on different parts of our body. These stages are all about the ways our minds and emotions develop, especially concerning our feelings and relationships.

Oral Stage (0-1 year)

Freud believed that babies focus a lot on their mouths. That's why they love to suck on things and put everything in their mouths!

Example: Baby Jamie is always comforted by a pacifier. When she's upset, the pacifier soothes her. As she grows, she transitions from pacifiers to thumb-sucking. As an adult, Jamie might develop habits that provide oral comfort, like nail-biting, chewing gum, or smoking. She might also seek instant gratification or comfort in stressful situations.

Anal Stage (1-3 years)

At this age, toddlers are often learning about potty training. Freud thought that how kids manage this stage could influence their personalities later on. Like, if they were too strict or too relaxed about it, it might show in how they behaved when they grew up.

Example: Toddler Ethan is potty training. His parents are very strict, giving him time-outs if he has an accident. Ethan might grow up to be a very orderly and punctual person, always wanting things to be in their right place. He might be a bit stubborn and dislike mess or disorder.

Phallic Stage (3-6 years)

Kids at this age start to notice differences between boys and girls. Freud believed this was a crucial time for developing our identities.

Example: Little Mia notices that she doesn't look like her brother and starts asking questions. She's curious about the differences and often imitates her mother's behaviors. Mia might develop strong identification with her mother, emulating feminine behaviors and roles. This stage might also play a role in how she understands gender roles as she grows up.

Latency Stage (6-puberty)

During this time, Freud thought kids took a sort of "break" from these intense developments. They focus more on school, friends, and other activities.

Example: Sam, who's 8, has started to focus more on school and making friends. He's joined a soccer team and spends less time with family and more time with peers. Sam's interactions with friends and his involvement in activities can shape his social skills and self-confidence. This is a phase where many foundational social behaviors and preferences are solidified.

Genital Stage (puberty-adulthood)

This is when people start to form strong relationships outside the family, especially as they grow into adults.

Example: Clara, in high school, starts dating and becomes more interested in forming romantic relationships. She talks to her friends about crushes and navigates the complexities of teenage relationships. Clara's experiences during this stage can influence her views on relationships, intimacy, and love. Positive or negative experiences can shape her approach to future romantic endeavors and her understanding of herself as a romantic partner.


Freud's ideas were groundbreaking, but they also raised many eyebrows. Some people thought he was spot on, while others believed he was way off. Today, not all psychologists agree with everything Freud said, but his theories laid the groundwork for many future discoveries in psychology.

2) Erikson's Psychosocial Stages Theory

a loving family

Erik Erikson, another influential thinker, came a bit after Freud. Instead of focusing on body parts, he looked at how people form relationships and their sense of self at different ages. Erikson believed that at each stage, we face a challenge or crisis that can shape our personality. Let's explore his stages:

Trust vs. Mistrust (0-1 year)

This stage is about learning to trust the world around us. Babies depend on caregivers for everything, and they need to feel safe.

Example: Baby Leo's parents respond quickly every time he cries, feeding him or cuddling him. Leo grows up feeling the world is a safe place and believing people are reliable.

Autonomy vs. Shame/Doubt (1-3 years)

Toddlers are learning to do things on their own. They need to feel they can handle basic activities independently.

Example: Toddler Ava wants to dress herself. Sometimes she wears mismatched socks or shoes on the wrong feet. Her parents cheer her efforts, even if it's not perfect. Ava grows up feeling confident in her abilities, willing to try new things without fearing mistakes.

Initiative vs. Guilt (3-5 years)

At this stage, kids start planning activities and come up with ideas. They need to feel their initiatives are okay and not feel guilty about being assertive.

Example: Little Jayden creates a game where he's a superhero. Sometimes he gets too excited and plays rough. If Jayden's creativity is encouraged but he's taught to play gently, he might become an innovative leader who respects others.

Industry vs. Inferiority (6-11 years)

School-age kids are learning to work and play with peers. They need to feel competent and successful in their tasks.

Example: Sarah struggles with math. Instead of saying she's bad at it, her teacher offers extra help, praising her efforts. Sarah learns the value of persistence and hard work, believing she can overcome challenges with effort.

Identity vs. Role Confusion (12-18 years)

Teenagers are figuring out who they are. They need to form a clear sense of self and role in society.

Example: Teenager Carlos is figuring out his passions. He loves art but also excels in soccer. He's torn between the two. Carlos learns the importance of self-discovery and might become someone who values balance in life.

Intimacy vs. Isolation (young adulthood)

Young adults are forming close relationships. They need to connect with others in meaningful ways.

Example: Maya has always focused on her career. Now in her late 20s, she desires close friendships and relationships but finds it hard to connect deeply. Maya might either learn the importance of deep relationships or might struggle with feelings of loneliness.

Generativity vs. Stagnation (middle adulthood)

Adults need to feel like they're contributing to the next generation, either by raising families or helping in the community.

Example: Mark, in his 40s, starts mentoring young professionals in his company, sharing his experiences and advice. Mark finds fulfillment in guiding others, feeling that he's contributing positively to the next generation.

Integrity vs. Despair (late adulthood)

Older adults reflect on their lives. They need to feel proud of their achievements and not regretful.

Example: Grandma Rosa, in her 80s, looks back on her life, remembering the good times and regrets. Rosa might find peace and wisdom in her memories, or she might struggle with feelings of regret and missed opportunities.


Erikson's stages show how our interactions and experiences at each age can mold who we become. Each stage offers its own lessons and challenges, all of which shape our understanding of ourselves and the world.

3) Piaget's Cognitive Development Theory

Jean Piaget, a Swiss scientist, spent a lot of time watching kids. He wanted to know how they think and learn about the world. He discovered that as kids grow, they go through different stages of understanding. Each stage is like a new step in figuring out the world around them.

He also came up with a theory of moral development that we dive into in another article.

Sensorimotor Stage (0-2 years)

Babies learn about the world through their senses and movements. They touch, taste, see, hear, and move to understand things.

Example: Baby Zoe shakes a rattle and is surprised by the noise it makes. She does it again and again to hear the sound. Zoe learns that her actions cause reactions. This is where babies start understanding cause and effect.

Preoperational Stage (2-7 years)

Young kids start using language and imagination more, but their thinking is still pretty basic and a bit egocentric, which means they mainly see things from their own point of view.

Example: Tommy gets upset when his sister takes his toy. He thinks she should know how he feels because he believes everyone feels the same as he does. Kids at this stage might struggle with seeing things from other people's perspectives. They're also learning about symbols, like how a drawing of a dog represents a real dog.

Concrete Operational Stage (7-11 years)

Kids start thinking more logically about concrete events. They can understand concepts like conservation: that quantity doesn't change even if the appearance does.

Example: When water is poured from a tall, thin glass into a short, wide bowl, Lucy knows it's the same amount of water, even though it looks different. This is a time where kids get better at problem-solving and understanding the world in a more organized way.

Formal Operational Stage (12+ years)

Teenagers and adults start thinking more abstractly and hypothetically. They can consider possibilities, think about the future, and solve problems in their heads.

Example: Max debates with his friends about what they would do if they were the president. He thinks about different scenarios and consequences. This is where people develop critical thinking skills and can imagine different outcomes and possibilities.


Piaget's observations help us understand how our thinking changes as we grow. From babies who learn by tasting and touching to teenagers who can dream big and think deeply, we're always learning and growing in how we understand the world.

4) Kohlberg's Moral Development Theory

Lawrence Kohlberg was curious about how people decide what's right and wrong. He came up with stages to describe how our sense of morality grows and changes over time. Just like climbing stairs, we can move up to a more advanced way of thinking about right and wrong.

Pre-Conventional Level

Obedience and Punishment (young children)

At this stage, kids think something is wrong because they get punished for it.

Example: Little Andy doesn't take a cookie because he's afraid he'll get in trouble. Andy might only behave well to avoid getting caught or punished.

Self-Interest (still young children, but a bit older)

Kids do what's best for them but might understand that others have needs too.

Example: Ella shares her toys with her friend, hoping she'll get a turn with her friend's toy in return. Ella might be nice to others, but mostly if she sees a benefit for herself.

Conventional Level

Interpersonal Relationships (often teenagers)

People act a certain way because they want to be seen as good by others. They care a lot about fitting in.

Example: Jake helps an elderly woman cross the street because he thinks it's what good people do and wants others to see him as kind. Jake may make choices based on what will make him liked or accepted by others.

Maintaining Social Order (older teenagers & many adults)

People understand and appreciate the importance of rules in society. They believe in doing their duty.

Example: Maria believes in paying taxes because it supports public services and keeps society running smoothly. Maria might prioritize keeping peace and order over individual needs.

Post-Conventional Level

Social Contract (some adults)

People see that rules are important but might change them if they don't benefit everyone.

Example: Alex votes to change a law that he thinks is unfair to a minority group. Alex believes in the greater good and thinks critically about societal rules.

Universal Ethical Principles (rare, few adults)

Some people have a personal set of ethical guidelines that might sometimes go against the law. If you're interested in ethics and morals, you might want to look into moral universalism, which argues that some morals are accepted in all cultures.

Example: Rosa Parks refused to give up her bus seat because of her deep belief in racial equality, even though it was against the rules. Individuals like Rosa might be willing to face consequences to stand up for what they truly believe is right.


Kohlberg showed us that our understanding of right and wrong isn't just about rules. It's about growing, thinking, and deciding what kind of person we want to be.

5) Vygotsky's Socio-Cultural Theory

child thinking about their world

Lev Vygotsky, a Russian psychologist, had a different take on how kids learn and grow. Instead of just looking inside the child's mind, he thought about the world around them. He believed our culture – things like language, tools, and traditions – plays a big role in shaping how we think.

Social Interaction

Vygotsky believed that learning happens first between people (like a child and an adult) before it happens inside the child. This means kids learn a lot from talking and playing with others.

Example: Little Timmy learns to count because his older sister plays shop with him. She's the shopkeeper, and he's the customer buying toys with pretend money. Playing and talking with family members, friends, and teachers can really boost a child's learning.

The Zone of Proximal Development (ZPD)

This fancy term describes what a child can do with help but can't do alone. It's like the space between what they know and what they're about to learn.

Example: Amy can't tie her shoes by herself, but with her mom's guidance, she can. Tying shoes is in Amy's ZPD. Knowing a child's ZPD helps adults teach them just the right things at the right time.


This is the support or guidance given by an adult or a more knowledgeable person. As the child learns, the support is gradually removed, just like scaffolding around a building.

Example: Dad shows Jamie how to ride a bike. At first, he holds the bike steady. Over time, he lets go more and more until Jamie rides on her own. With the right support, kids can master new skills faster and with more confidence.

Cultural Tools

These are things in our culture, like language or tools, that help shape our thinking. Vygotsky believed that these tools play a big role in how we learn and see the world.

Example: In school, Ava learns to use a calculator. This tool helps her solve math problems faster and in a different way. The tools and traditions in our culture can influence how we think, solve problems, and interact with others.


Vygotsky's ideas remind us that learning isn't just an inside job. The people around us, the tools we use, and the culture we live in all play a part in how we grow and understand the world.

6) Bandura's Social Learning Theory

Albert Bandura, an American psychologist, had a unique idea about how we learn. He believed that a lot of our learning happens by watching and copying others. Imagine learning a dance move by watching a video or picking up a catchphrase from your favorite show. That's Bandura's idea in action!

Observational Learning

This is learning by watching and then imitating or copying what we see. Bandura believed this is a major way kids learn.

Example: Billy sees his friend say "please" and "thank you" and notices people are happy with his friend's manners. Billy starts using those polite words too. Kids might pick up both good and bad behaviors by watching others.

The Bobo Doll Experiment

This is a famous study by Bandura where children watched an adult behave aggressively towards a toy called a Bobo doll. Later, many of these children copied the aggressive behavior.

This experiment showed that kids can learn behaviors, even aggressive ones, just by watching.


This is a person's belief in their ability to succeed or accomplish something. Bandura believed that if you think you can do something, you're more likely to try and succeed.

Example: Sara watched her big brother learn to play the guitar. She believes she can learn too, and with practice, she does! Believing in ourselves can push us to try new things and achieve our goals.

Reinforcement and Punishment

Bandura said that rewards (or reinforcements) can make a behavior more likely to happen again, while punishments can make it less likely.

Example: If Leo gets a gold star every time he reads a book, he might read more. But if he's told off for drawing on the walls, he might stop. Rewards and consequences shape our choices and habits.


Bandura's theory shows that we're not just learning machines. We watch, think, and choose based on what we see and feel. It reminds parents, teachers, and friends to be good role models because others are always watching and learning.

7) Bowlby's Attachment Theory

Have you ever noticed how babies get really attached to their parents or guardians? That special bond is what psychologists call "attachment." This bond is super important for how children feel and behave as they grow up.

John Bowlby believed that children have a built-in drive to form attachments because it helps them survive. These early attachments affect a child's future relationships.

Example: If baby Leo's needs are consistently met, he learns that the world is a safe place and that people can be trusted. Strong, healthy attachments early on can lead to better relationships and mental health in the future.

8) Ainsworth's Attachment Theory

Mary Ainsworth expanded on Bowlby's ideas. She identified specific styles of attachment: Secure, Avoidant, Ambivalent, and Disorganized.

Secure Attachment

A child with secure attachment feels confident that their caregiver will be available and responsive to their needs. They are comfortable with intimacy and independence, balancing the two.

Example: When little Emma is playing and her mother steps out of the room, she may notice and might feel a bit upset. However, when her mother returns, Emma is quickly comforted and goes back to playing happily.

Avoidant Attachment

A child with avoidant attachment seems to avoid or disregard their caregiver. They don't appear too distressed when the caregiver leaves and may avoid them upon return.

Example: When Max's dad leaves the room, Max doesn't seem bothered at all. Even when his dad returns, Max doesn’t show much interest and continues playing by himself without acknowledging his dad's return.

Ambivalent Attachment (or Anxious-Resistant Attachment)

A child with ambivalent attachment becomes very distressed when the caregiver leaves. However, upon their return, the child may both seek closeness and resist it, showing mixed feelings.

Example: When Sophia's grandma leaves the room, Sophia becomes very upset. But when grandma returns, Sophia might run to her, but then push her away or become fussy when picked up.

Disorganized Attachment

A child with disorganized attachment shows no consistent way of coping with the stress of the "Strange Situation" (Ainsworth's method for studying attachment). Their behaviors may seem contradictory or confused.

Example: When Mia's aunt leaves and then returns, Mia might approach her with a flat, depressed expression or might suddenly freeze or fall to the floor. Her actions seem unpredictable and don't fit into the other categories.

Modern Attachment Research and Implications for Parenting

Today, scientists continue to study attachment. They've found that a child's attachment style can influence many parts of their life, from friendships to how they feel about themselves.

Research shows that kids with secure attachments tend to be more confident, understand their feelings better, and handle challenges more positively.

For parents, understanding attachment can help guide how they connect with and support their child. Being responsive, consistent, and loving can promote secure attachment and its benefits.

In a nutshell, attachment is more than just a close bond; it's a foundation for a child's emotional health, self-worth, and future relationships. As we can see, the love and care we give to kids when they're little can shape their whole world!

9) Bronfenbrenner's Ecological Systems Theory

Imagine your life is like a big set of nested dolls. Each doll, or layer, represents a different part of your world. Urie Bronfenbrenner came up with this idea to explain how different parts of our environment shape us. Let's break it down!

ecological systems illustration


This is the closest layer to a person. It's made up of direct relationships, like family, school, and friends.

Example: Jamie's relationship with her parents, her classroom, and her best friend are all parts of her microsystem. Good relationships in this layer can make Jamie feel loved and confident. Troubles here, like bullying, can hurt her feelings or self-esteem.


This is how the parts of the microsystem interact with each other.

Example: How Jamie's parents communicate with her teacher is part of the mesosystem. If Jamie's parents and teacher work well together, it can help her do better in school and feel more supported.


This layer contains settings or places that Jamie might not directly be a part of, but they still affect her. Think of things like her parents' jobs.

Example: If Jamie's mom has a stressful job and is often tired, it can affect their time together at home. Even though Jamie doesn't go to her mom's job, changes there can still shape her daily life and feelings.


This is the big picture! It's about the larger culture and society, including beliefs, customs, and laws.

Example: The country's beliefs about education and the importance of school can influence Jamie's own views. The values and beliefs of the bigger world can shape Jamie's understanding of right and wrong, her goals, and how she sees herself.


Time is also a factor! This layer is about how personal and environmental events influence a person's development over time.

Example: Jamie moving to a new city when she was younger or the rise of technology during her teen years. Major life changes or events in society can shift Jamie's experiences, beliefs, and relationships.


Bronfenbrenner's theory helps us see that our lives aren't just shaped by our immediate surroundings. There's a whole wide world out there, with many layers, all playing a part in making us who we are. It's like a big puzzle, and every piece matters!

10) Contemporary Theories

Even as we've learned a lot from older theories, new ones keep popping up! Modern science and changes in our world have brought forward new ideas that are reshaping how we understand our growth and behavior.

Neurodevelopmental Perspectives on Human Growth

This view looks at how our brain grows and changes to understand our development. It's all about the connections and wiring in our brain!

Example: Imagine your brain is like a city with lots of roads. As a baby, only a few main roads are built. As you grow, more roads (or connections) form, making the city busier and smarter. By understanding how our brains develop, we can find better ways to learn, handle emotions, and even deal with problems like ADHD or autism.

Impact of Technology and the Digital Age on Development Theories

As we live more of our lives online and with gadgets, researchers are curious about how this tech-world affects how we grow and think.

Example: Remember when kids used to play with just toys and bikes? Now, many kids grow up swiping on tablets or learning from YouTube. This changes how they play, learn, and even socialize. The digital age might be helping kids become great multitaskers or learn faster. But, it might also be affecting their social skills or attention spans.

Cultural and Cross-Cultural Considerations in Development

This perspective understands that people's growth and behavior are deeply affected by their culture. So, what's "normal" in one culture might be different in another.

Example: In some cultures, kids start helping with housework or farming very early. In others, kids might focus more on school and sports. These differences can shape what skills kids learn and value. Recognizing these cultural differences helps us understand that there's no single way to grow up. It celebrates diversity and reminds us to be open-minded.


To wrap it up, while old theories give us a solid base, these new perspectives remind us that our world is ever-changing, and so is our understanding of how we develop in it. It's like adding new chapters to an already awesome book!

Practical Implications of Development Theories

Think of these theories as tools in a toolbox. When you know how to use them, you can build better classrooms, therapy sessions, and even families! There probably isn't one theory that is totally correct, but they all can work together to help us better understand ourselves and others.

Application in Educational Settings

Teachers might use Piaget's stages to know when kids are ready for certain lessons. Like, younger kids might learn math with blocks and toys, while older ones dive into more abstract problems.

By matching lessons to how kids naturally grow and think, we can make school more engaging and effective!

Importance in Therapy and Counseling

Therapists and counselors use development theories to understand their patients better and guide their treatment plans.

Remember Erikson's stages? A teenager in therapy might be struggling with finding their identity (a big Erikson stage). The therapist can use this knowledge to help them navigate this tricky time.

Therapy becomes more focused and helpful when it's rooted in a deep understanding of human growth stages.

Parenting Strategies Informed by Developmental Theories

Moms, dads, and other caregivers can use these theories to raise their kids in ways that align with their natural growth and challenges.

Parents might use attachment styles to build strong, loving bonds with their babies, ensuring they feel safe and loved.

By understanding what their child is going through at each age, parents can be more supportive, patient, and effective in their parenting.

In short, these theories aren't just for textbooks. They're powerful tools that, when used right, can make a big difference in our schools, therapy rooms, and homes. It's like having a map for the adventure of growing up!


Development isn't just for babies or little kids. It's a journey we all travel, from the day we're born to our very last steps. Throughout this adventure, there are many paths and stages, each with its own set of challenges and joys. The different theories we've explored are like guides that help us understand this journey better.

Whether it's the mysteries of our minds with Freud, the steps of growth with Erikson, or the wonders of our changing world in the digital age, each perspective offers a unique view of how we become who we are. And the best part? These theories aren't just for scientists or teachers. They're for everyone – parents, friends, and even curious minds like you!

By understanding these theories, we're better equipped to help ourselves and others. It's like having a compass in the vast landscape of life, guiding us to be more compassionate, patient, and insightful. So, as we continue to grow and evolve, let's remember to cherish every stage, learn from each experience, and always be open to the wonders of development.

Reference this article:

Practical Psychology. (2023, August). 9+ Development Theories (Definitions + Examples). Retrieved from https://practicalpie.com/development-theories/.

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