Background: Patients' pretreatment preferences can influence outcomes of nonpharmacologic treatments for musculoskeletal pain. Less is known about how patients' treatment preferences change following exposure to treatment. Objective: To examine the effect of exposure to treatment and change in disability and pain on treatment preference ratings of two exercise-based treatments for people with chronic low back pain (LBP). Design: Secondary analysis of a subsample of participants from a randomized clinical trial. Setting: Academic research setting. Participants: Individuals with chronic LBP (n = 83). Interventions: 6 weekly sessions of motor skill training (MST) or strength and flexibility exercise (SFE). Main Outcome Measures: Prior to treatment, participants completed a treatment preference assessment measure (TPA) describing MST and SFE. Participants rated four attributes (effectiveness, acceptability/logicality, suitability/appropriateness, convenience) of each treatment on a 5-point Likert scale (0–4) with higher scores indicating higher ratings. An overall preference rating was calculated as the mean of the attribute ratings. The TPA was administered 12 months post treatment to reassess participants' ratings of the treatment they received. Results: Participants who received MST rated their preference for MST higher 12 months post treatment and participants who received SFE rated their preference for SFE lower. Smaller improvements (to worsening) in pain were associated with a reduction in preference ratings in the SFE group, whereas the MST group generally increased their ratings regardless of pain. Changes in disability were not related to changes in preference ratings. Conclusions: Participants changed their preference ratings of two exercise-based treatments for LBP after exposure to the treatment. Participants who received the less familiar MST viewed this treatment more favorably 12 months post treatment, and this change was less contingent on changes in disability/pain than for participants in the SFE group. Assessing preference ratings at various times during treatment is crucial to understand a person's preference for and perceptions of a treatment.