Yes / This paper demonstrates the practical application of process mapping principles as a model for evaluating NHS improvement. The NHS improvement in question was the merger of three crisis resolution teams within an NHS trust in 2012. The aims were to improve overall operational efficiency and enhance multidisciplinary working to meet operational targets. This paper examined changes following the merger to capture the effects of service improvement and the reality of the patient journey. Methods: A pooled cross-sectional approach, using six years of aggregated hospital data, was taken. To achieve operational efficiency, a process map of referrals, readmissions, length of stay and waiting times for crisis resolution team assessments was examined. Prevalence of clinical referral rates and disease classification before and after the merger were compared. Conclusion: Between 1 April 2009 and 30 March 2015, length of stay and readmissions for patients to crisis resolution team rates reduced. Operational sustainability and capacity was enhanced through the redistribution of clinical human resources. Multidisciplinary skill mix (e.g. through improved team composition) also improved.