The short version
The 4 principles many of us learned (express empathy, develop discrepancy, roll with resistance, support self-efficacy) were dropped in the 3rd edition. The current framework is 4 tasks: engaging, focusing, evoking, and planning. They overlap and repeat; they are not steps.
"Resistance" is gone as a term. Most of what it described is sustain talk, one side of a client's ambivalence. The rest is discord in the relationship. Both respond to how the coach behaves.
The spirit has grown from collaboration, evocation, and autonomy to partnership, acceptance, compassion, and empowerment.
MI's effects on health behavior are real but modest, and they vary a lot across studies and practitioners.
What changed, and why
William Miller's 2023 review traces how MI has evolved since 1983 (Miller, 2023). Three changes matter most for coaches.
From principles to tasks. The first 2 editions of the book described general principles. The 3rd edition dropped them in favor of 4 processes. The 4th edition (Miller & Rollnick, 2023) calls them "the four tasks of MI" and gives each a question as its chapter title: - Engaging: "Can we walk together?" - Focusing: "Where are we going?" - Evoking: "Why would you go there?" - Planning: "How will you get there?"
Miller (2023) notes that the tasks "may sound linear and sequential," but in practice they are "more iterative and flexible." Goals shift, planning overlaps with evoking, and you may need to re-engage at any point.
From resistance to sustain talk and discord. The authors came to feel that "resistance" blamed clients, implying deliberate obstruction or pathology. Theresa Moyers observed that most of what had been called resistance was "simply sustain talk," just one side of a person's ambivalence. Sustain talk is about the change itself ("I don't have time to cook"). Discord is about the relationship and often includes "you" ("You don't get how busy I am"). Miller (2023) reports that both predict poorer outcomes when they persist, and both respond to the practitioner's style. The 4th edition gives the topic its own chapter, "Responding to Sustain Talk and Discord." That is a more useful frame than "rolling with" something: if discord rises, the coach's behavior is part of the picture.
A broader spirit. The 2nd edition named collaboration, evocation, and autonomy. The 3rd edition described partnership, acceptance, and evocation and added compassion, which Miller defines as "a conscious commitment to the well-being and best interests of the client." Compassion was added because MI techniques can be used in self-serving ways. Miller (2023) also writes that the authors' "understanding of evoking has expanded to empowerment," meaning helping people realize and use what they already have. He flagged genuineness as an area the 4th edition would develop.
What the evidence shows
By 2022, more than 1,900 controlled trials and more than 200 meta-analyses or systematic reviews of MI had been published. Between two-thirds and three-quarters of trials report significant benefits, average effects are small to medium, and results vary widely across studies, sites, and practitioners (Miller, 2023).
In medical care settings, Lundahl and colleagues (2013) pooled 48 randomized trials with 9,618 participants and found a "modest advantage" for MI (odds ratio 1.55). MI looked promising for alcohol and tobacco use, sedentary behavior, self-monitoring, and confidence in change, and it worked in brief consultations. It was not particularly effective for eating disorders or self-care behaviors.
The more cautious view comes from Frost and colleagues (2018), who reviewed 104 reviews, including 39 meta-analyses. Most of the evidence (128 of 155 comparisons) was rated low or very low quality. Moderate-quality evidence for small, mostly short-term benefits appeared in 11 comparisons, including less drinking and more physical activity. They also flagged poor reporting of whether MI was delivered as intended.
Two takeaways. Most of this research involves clinicians and counselors, not coaches, so expect modest effects and treat MI as a way of having the conversation, not a technique that guarantees change. And Miller (2023) names one known caution: MI may delay or reduce improvement for people who already arrive high in readiness or confidence. For those clients, move to planning.
Using it with clients
Respond to sustain talk as ambivalence, not opposition. For example, a client might say, "I know I should cook more, but evenings are chaos." A double-sided reflection holds both sides: "Part of you wants more home-cooked dinners, and part of you knows evenings are already stretched thin."
Treat discord as a signal about the relationship. "It sounds like I got ahead of you. Let's back up to what matters most to you right now."
Let the client set the focus. "We have a few things on the table today. Where would you like to start?"
Evoke before you plan, and ask before you inform. "Why might this be worth doing now?" When information would help, ask first: "Would it be okay if I shared what the national guidelines say?"
If change talk is strong and the client is ready, don't drag them back through evoking. Planning is the respectful move.
Where coaching stops
MI is widely used in addiction treatment and psychotherapy. Coaches use it as a communication style for client-chosen wellness goals, not to treat substance use disorders, depression, eating disorders, or other mental health conditions. When those show up, refer to a mental health professional. When a conversation turns to medication or treatment decisions, the coach can explore the client's concerns but sends the clinical question to the physician, prescriber, or pharmacist.
Go deeper
The Advanced Motivational Interviewing package, in development, covers the 4 tasks, responding to sustain talk and discord, and practice with feedback.
References
Frost, H., Campbell, P., Maxwell, M., O'Carroll, R. E., Dombrowski, S. U., Williams, B., Cheyne, H., Coles, E., & Pollock, A. (2018). Effectiveness of motivational interviewing on adult behaviour change in health and social care settings: A systematic review of reviews. PLOS ONE, 13(10), e0204890. https://doi.org/10.1371/journal.pone.0204890
Lundahl, B., Moleni, T., Burke, B. L., Butters, R., Tollefson, D., Butler, C., & Rollnick, S. (2013). Motivational interviewing in medical care settings: A systematic review and meta-analysis of randomized controlled trials. Patient Education and Counseling, 93(2), 157–168. https://doi.org/10.1016/j.pec.2013.07.012
Miller, W. R. (2023). The evolution of motivational interviewing. Behavioural and Cognitive Psychotherapy, 51(6), 616–632. https://doi.org/10.1017/S1352465822000431
Miller, W. R., & Rollnick, S. (2023). Motivational interviewing: Helping people change and grow (4th ed.). Guilford Press. https://www.guilford.com/books/Motivational-Interviewing/Miller-Rollnick/9781462552795
