The document summarizes the research of the XSIM Team on facilitating scientific collaborations through delegating identity management. It provides context on how scientific collaborations have evolved from localized to remote and large-scale. It identifies barriers to identity management like historical inertia, risk aversion, and compliance requirements. The document then presents the XSIM VO Identity Model and examples of incremental identity delegation approaches used at facilities like NERSC and XSEDE to reduce costs while maintaining security. It concludes that virtual organizations are essential to science and strategies exist to incrementally increase trust and delegation of identity functions.