Forensic mental health care in the UK has undergone a rapid expansion since the late 1990s. In medium secure units (MSUs), there is growing emphasis on developing care pathways without much theoretical underpinning. We developed a concept of 'Milestones to Recovery' (MTR) to measure progress through the MSU pathway. Our aim was to validate the MTR framework. Our hypotheses were that patients scoring higher on the MTR Scale would be more likely to be aggressive to others in the following 6 months and resident in the acute areas of the unit and that those scoring lower would be more likely to be discharged within 6 months of the assessment. An MTR scale was developed to enable the investigation of the validity of the MTR framework and evaluated with staff evaluations of 80 resident patients using a prospective, longitudinal and naturalistic design. The results suggest that the MTR framework is valid in discriminating between different stages on the MSU pathway. Therapeutic engagement was particularly important in terms of progress through the MSU, whereas current behaviour was important in predicting future aggression. Further research is required to test the MTR framework across different levels of security, with larger samples and within different populations. Provides a framework to map progress through the service. Identifies key factors that influence recovery and rehabilitation. Potential to promote dialogue between patients and staff, and enhance motivation.