Background: The integration of community health and social care services has been widely promoted nationally as a vital step to improve patient centred care, reduce costs, reduce admissions to hospital and facilitate timely and effective discharge from hospital. The complexities of integration raise questions about the practical challenges of integrating health and care given embedded professional and organisational boundaries in both sectors. We describe how an English city created a single, integrated care partnership, to integrate community health and social care services. This led to the development of 12 integrated neighbourhood teams, combining and co-locating professionals across three separate localities. The aim of this research is to identify the context and the factors enabling and hindering integration from a qualitative process evaluation. Methods: Twenty-four semi-structured interviews were conducted with equal numbers of health and social care staff at strategic and operational level. The data was subjected to thematic analysis. Results: We describe three key themes: 1) shared vision and leadership; 2) organisational factors; 3) professional workforce factors. We found a clarity of vision and purpose of integration throughout the partnership, but there were challenges related to the introduction of devolved leadership. There were widespread concerns that the specified outcome measures did not capture the complexities of integration. Organisational challenges included a lack of detail around clinical and service delivery planning, tensions around variable human resource practices and barriers to data sharing. A lack of understanding and trust meant professional workforce integration remained a key challenge, although integration was also seen as a potential solution to engender relationship building. Conclusions: Given the long-term national policy focus on integration this ambitious approach to integrate community health and social care has highlighted implications for leadership, organisational design and interprofessional working. Given the ethos of valuing the local assets of individuals and networks within the new partnership we found the integrated neighbourhood teams could all learn from each other. Many of the challenges of integration could benefit from embracing the inherent capabilities across the integrated neighbourhood teams and localities of this city.