(The following is my own understanding and practice of IFS, and may include elements that conflict with the standard model. In an attempt to keep these brief I won’t be going into much theory, and focus on what seems to work best for myself and my clients)
Internal Family Systems is a form of therapy that treats psychological or emotional difficulty as the result of disagreements between the “parts” that make you who you are. Sometimes these parts make themselves known as (disagreeing/discordant) thoughts, other times as (conflicting/painful) emotions. A variety of labels can be useful to identify and understand their effects and interactions; in the classic model, these are Exiles, Firefighters, and Managers, as well as the Self, which is the “part” that your conscious mind remains associated with even amidst fragmentation.
But there are many forms IFS can take, or layers that can be applied onto each other. For some, characterizing their parts as actual family members (Child, Teenager, Adult) is very useful. For others, a starship crew (Security, Engineering, Science, Captain) makes for easier internal communication. Whatever form these parts take, IFS can be valuable for many purposes, but the most straightforward one is simple “emotional integration,” which is to say, conversely, feeling more like a unified individual rather than struggling with emotional turmoil over some looming decision or past action.
The path to integration looks something like this:
Finally, Integration comes from practice, patience, and trust. As I said, it’s not always a steady progression. We encounter new things, life gets messy, parts get out of sync. But trust yourself, be patient with yourself, practice the skills, and the rest of you will be ready and waiting to re-integrate until you feel like unified again.
(You can learn more about IFS from this more in-depth article)