TIST is a cutting edge, "parts" model of psychotherapy.  There are numerous therapies, including Internal Family Systems, Transactional Analysis and others, that are based on the concept that personality consists of many different parts.

These therapies achieve results by facilitating cohesion and harmony between the various parts. 
For example, we can see how “parts” affect the life of a client named Jim.  Jim is involved in an extra marital affair.

Part of him, feeling guilty, resolves to end the affair immediately.  But another part - a stronger part - wants to keep the affair going.

Unfortunately the second part is threatening the integrity of Jim’s marriage; it’s only a matter of time before his wife will start asking about his increasingly long and inexplicable absences.

A “parts therapy” approach to treatment would help Jim resolve the conflict between his inner personalities by addressing each part's needs and concerns and helping them all to get on the same page to either end the marriage or end the affair.

As a certified TIST practitioner, I can use the parts model to effectively treat much more than internal conflict.

TIST penetrates into the deepest levels of personality, helping clients to resolve developmental trauma, addictions, feelings of emptiness, depression, anxiety, interpersonal issues and more.