Geographically dispersed integrated project teams collaborating in virtual environments face many challenges in the successful completion of projects, particularly when the project teams are non-homogenous. Model-based process improvement provides a viable way for organizations to improve the capability of software development teams, including the effectiveness of leaders in charge of integrated teams operating in virtual environments. Evolving a Process Reference Model (PRM) covering this activity has therefore been the subject of an on-going research project at Griffith University. The outcomes of this project may prove useful as a means to improving leadership capability, particularly in relation to complex, multidisciplinary teamed projects conducted in virtual environments. This paper introduces the nature and scope of the Process Reference Model and presents the preliminary findings of the validation phase of the PRM development.