The objective of this study is to describe the rationale, design and selected baseline results of a 2-year randomized-controlled trial (RCT) on the effects of physical activity counseling in community-living older people. After a four-phase screening and data-collection process targeting all independently living people in the city center of Jyväskylä, Finland, six hundred and thirty-two 75-81-year-old cognitively intact, sedentary persons who were able to move independently outdoors at least minimally and willing to take part in the RCT were randomized into intervention and control groups. At baseline, over half of the subjects exercised less than two to three times a month and two-thirds were willing to increase their physical activity level. The desire to increase physical activity was more common (86%) among subjects with mobility limitation compared with those without (60%, P=0.004). The intervention group received an individualized face-to-face counseling session, followed by phone contacts every 3 months throughout the intervention. The study outcomes include physical activity level, mobility limitation, functional impairments, disability, mood, quality of life, use of services, institutionalization and mortality. The screening and recruitment process was feasible and succeeded well, and showed that unmet physical activity needs are common in older people.