Portfolio Change Impacts on People – Change the Critical Path?

Project Management methodologies like PMBOK consider organizational change impacts only from a project, rather than a portfolio perspective.  In setting the critical path for a portoflio of projects that are interdependent do you consider the extent of change that can be absorbed by the same target group?  Is this a critical risk issue that needs to be part of all project management plans.  We worked with a government department that had embarked on an aggressive transformation program, that involved significant change in technology and service delivery networks.  We developed a change impact methodology that aggregated for each occupational group and organization the full extent of change impacts across all projects in the portfolio.  We found that the timing for implementation was overly aggressive, potentially causing change overload.  Using risk methodologies we identified those groups and projects that needed dramatic change efforts, or alternatively the timeline for portfolio needed to be re-adjusted.  Interestingly, enterprise project management offices in the federal government, focus only on controlling for each project the three standard elements of project management:  scope, time and cost.  There is short shrift given to looking at organization change impacts as a critical factor.