The Cross-sector Innovation Initiative (CSII) environmental scan compiles key findings from a literature review, secondary data analysis and key informant interviews on cross-sector collaboration between the public health, healthcare and social services sectors. Findings highlight the roles that different sectors can play in collaboration, a continuum of collaboration and factors that facilitate or impede cross-sector collaboration. Facilitating and impeding factors are organized into three categories: community/environmental factors, organization factors and collaboration factors. This tool was developed collaboratively by the Center for Sharing Public Health Services and the Public Health National Center for Innovations. Publication number PHSharing/19-11-V1.