The IFS evidence base deserves real measurement.
We intend to build it.
Parts Companion is developing the first validated, observer-rated, automatable process measure for Internal Family Systems therapy — built on what we believe is the largest corpus of de-identified and research-released IFS session recordings in existence, and validated in the open, with the field.
We start from a conviction, not a market.
Parts Companion is built by Evolve, an organization dedicated to the evolution of human consciousness — to the reduction of inner suffering and the facilitation of genuine personal transformation. We believe the great inner technologies — disciplined, teachable methods for working with the interior life — deserve the same infrastructural seriousness the world grants its outer technologies.
Internal Family Systems is among the most promising of these. It gives people a workable map of their own inner world, and it gives clinicians a humane, non-pathologizing method that practitioners and clients love. But a modality only reaches the people who need it when institutions trust it — and institutions trust evidence.
So our research program is not a side project or a marketing exercise. It is the most direct contribution we can make to the mission: help IFS earn the institutional standing its clinical reality deserves, by building the measurement infrastructure that every future trial, grant application, and training program will need.
IFS is widely practiced, deeply loved — and absent from every list that allocates legitimacy.
Fields move when measurement arrives.
Motivational Interviewing did not earn its trial base by charisma. The MITI coding system became the de facto standard for MI trial integrity, and the modality's evidence co-evolved with its measurement. CBT's competence measures played the same standardizing role. Fidelity reporting is now effectively required for a fundable psychotherapy trial.
And observational coding is the documented pain point: slow, expensive, dependent on extensively trained human raters — "impractical for routine mental health care," in the literature's own words. The last five years proved automation can close that gap: LLM- and ML-based fidelity scoring, benchmarked against human consensus, published in venues from Implementation Science to JAMA Psychiatry.
IFS never got its MITI. We intend to build it — automated from day one, and validated to the standards of the process-research literature: human inter-rater reliability first, machine agreement second, outcome linkage last, in that order, with each claim gated on the evidence behind it.
A data asset and an instrument the field has never had.
Parts Companion records, transcribes, and structures real IFS sessions as its core product. Years of that work have produced what we believe is the largest repository of de-identified and research-released IFS therapy session recordings anywhere — longitudinal, naturalistic arcs of real clients over months of work, not lab vignettes. On top of it, we have built the apparatus a measurement program needs.
Four studies, in the order the literature demands.
Our protocol follows the fifty-year playbook of psychotherapy process research — and the published sequencing of the groups that did this credibly for other modalities: measurement validity first, outcomes later. Nothing is claimed ahead of its study.
We publish what didn't work
Our pilot's most instructive results were negative. Dramatic in-session "breakthroughs" did not corroborate against clients' own later reports — while quiet signals did: enacted between-session behavior change, growing somatic access, sustained experiential depth. Raw "Self-energy" estimates inflate for IFS-fluent clients. We regard findings like these as assets, and they will appear in anything we publish.
Fluent clients can't fool the good signals
The hardest problem in IFS process measurement is that every marker is forgeable in a single session by a fluent, Self-like managerial part. Our instrument is built around that problem: claims are coded as claims, confirmation happens only against the arc, and our pilot's most promising session-level measure discriminated genuine deepening from fluent performance in both low- and high-fluency test clients.
Therapy transcripts are among the most sensitive data that exist. We act like it.
The research program runs under a formal protocol whose ethics section is binding on every study. These are its load-bearing commitments:
We cannot — and should not — do this alone.
Analytical validation is something we can produce; clinical validation is something only the field's trial-running institutions can anchor. The organizations that fund, run, and govern IFS research hold exactly what this program needs, and we hold exactly what their trials have lacked. That is a trade worth a conversation.
The full papers behind this page.
Everything summarized above is developed at length in a set of internal research documents. We share them with research institutions, prospective collaborators, and serious colleagues — available upon request.
If you are working on the IFS evidence base, we would like to meet you.
Researchers, research funders, training institutions, trial teams: the whitepapers, the codebook, and an honest account of where the program stands are yours for the asking.