Neurogenic claudication due to spinal stenosis is a common cause of disability in older adults. Conservative treatments are a favourable treatment option. This paper describes the development and delivery of the BOOST (Better Outcomes for Older adults with Spinal Trouble) intervention, a physiotherapist-delivered physical and psychological intervention for the management of neurogenic claudication in older adults. The BOOST intervention is being tested in a multi-centre, randomised controlled trial in UK National Health Service Trusts; delivered by physiotherapists registered with the Health and Care Professionals Council. Participants are aged 65 years or older, registered with a primary care practice, and report symptoms consistent with neurogenic claudication. Intervention content and delivery was initially informed by clinical and patient experts, research evidence, and behaviour change guidelines; and refined following an intervention development day attended by researchers, health professionals, and Patient and Public Involvement representatives. The BOOST intervention comprises 12 group sessions, promoting sustained adherence with a long term home and physical activity programme. Each session includes education and group discussion, individually tailored exercises, and walking. Initial exercise levels are set at a one-to-one assessment. Continued home exercise adherence and increased physical activity following completion of the sessions is facilitated through support telephone calls. Trial registration ISRCTN12698674.