People will likely struggle with or develop their identity throughout their lives, but a lot of major changes occur during adolescence. Adolescence is when we first start to describe ourselves in more complex ways and see ourselves as more than just what we have, do, or like. For example, older children are more likely to tell you about their personality versus younger children, this is because it is not until adolescence that people develop the cognitive abilities to have substantial recognition of themselves as individuals. How one views themselves is also impacted by puberty which is related to biological changes that one goes through. So, not only are you able to think about who you are via cognitive ability, but your body and society’s expectations on who you are/should be are changing around the same time as well. This can lead to imagining different possible and future selves and experimenting with different roles and identity expression, which are all things you first start to do at adolescence. 

Autonomy is a concern that resurfaces again and again throughout the course of someone's life. A toddler might take its first steps into autonomy by exploring their surroundings on their own, and an adult might have to redevelop and independence after a divorce. When an adolescent starts to develop their own sense of autonomy, friction may arise with their parent or guardian. An emotionally independent young person might find it frustrating having to follow a parent’s rules, but the parent may feel like they still have say over their child because the child is financially still dependent on them. This conflict and delayed independence can be linked to economic hardships where a child may be financially dependent on their parent or guardian into early adulthood. 

Developing autonomy during adolescence is related to cognitive ability and puberty changes. Seeking independence may be naturally linked to physical maturation and the desire to ‘leave the nest’. Puberty can also start physical changes that lead to adults to giving the adolescent more responsibilities because they not look older and more able to handle things. 

When discussing adolescent intimacy, remember that intimate relationships aren't just romantic teen to teen relationships. Intimacy can also extend from adolescent to parent, sibling, or an adult outside of the immediate family. Adolescence changes what someone looks for in a friend (personality plays a larger role vs childhood surface similarities) and increases their capacity to have intimate friendships with multiple sexes. Adolescent intimacy and friendships can be beneficial to one's health and also signal potential future success or failures in relationships and intimacy.

Positive sexuality in adolescence consists of the adolescent being comfortable with their maturing body, accepting their feelings of arousal as normal and appropriate, needing to be comfortable about their choices whether or not to participate in sexual activities, and the understanding and practice of safe sex.

Puberty and adolescent sexuality are strongly linked. Puberty kickstarts the sex drive in early adolescence and leads to a lot of hormonal changes in the body. It's not until puberty that people become capable of sexual reproduction, but people can feel sexual arousal before puberty and have the desire to physically explore that. Secondary sex characteristics develop at puberty and in many cultures signal that someone is no longer, at least physically, a child. Hormonal changes can also affect the brain and impact the ways that we experience emotion and process social information.

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