To achieve better quality and efficiency of care and services for clients, social and health care professionals should be educated to adopt an interprofessional way of working and thinking. This requires the development of an interprofessional identity alongside a professional identity. The process must be facilitated comprehensively in social and health care operations. The aim of this observational and cross-sectional mixed-method study was to investigate readiness and perceived development needs concerning interprofessional work among social and health care students and professionals. Furthermore, the aim was to examine the formation of an interprofessional identity in relation to the theoretical framework of interprofessional socialization. In our results, development needs, expressed by the respondents, were categorized at the system, profession, and individual levels of social and health care. Although, positive attitudes were established among students and professionals, our findings demonstrate that the formation of an interprofessional identity requires comprehensive support from social and health care operations. Interprofessional identity can be enhanced especially by applying and developing interprofessional education and lifelong learning.