Walking treatment is recommended for improving intermittent claudication (IC), a debilitating symptom of leg pain caused by peripheral arterial disease. However, center-based exercise programs offered in a community or hospital setting are often not implemented or adhered to. We developed a home-delivered behavior-change intervention, MOtivating Structured walking Activity in Intermittent Claudication (MOSAIC), to increase walking in people with IC. A feasibility randomized controlled trial with nested qualitative interviews involving a subsample of trial participants was conducted. Feasibility criteria evaluated participant recruitment and retention; suitability of proposed outcome measures; and acceptability and adherence to the intervention and trial. Participants (adults aged ≥18 years diagnosed with IC identified from vascular outpatient clinics) were randomized 1:1 to receive MOSAIC treatment (two 60-minute home-based sessions and two 20-minute booster telephone calls incorporating behavior-change techniques) or an attention-control comparison. Outcomes (baseline and 16-week follow-up) included the 6-minute walking distance (meters), pedometer-assessed daily walking activity (steps/d), health-related quality of life, physical functioning, and beliefs about walking treatment, peripheral arterial disease, and self-regulatory processes. Twenty-four participants (mean age: 66.8 ± 9.4 years, 79% male) were included. Feasibility criteria achieved were recruitment rate (25%), participant retention (92%), and adherence to assigned treatment or attention-control sessions (71%). Missing data rates were <10% for all outcomes except for baseline daily walking activity (36%). The trial protocol and interventions were acceptable to participants and the clinician. In conclusion, the MOSAIC trial was feasible to conduct, with the exception of high missing pedometer data. The intervention is an acceptable approach to facilitate walking among people with IC.