In a business environment increasingly pressured by time efficiency as a key competitive advantage, schedule management in projects and programs has become a critical competency. However, project and program schedule it is still an immature discipline in many project-based organizations. Schedules are very often developed based on empirical approaches, without following well-established international standards and best practices. Many organizations do not develop their own internal scheduling standards to support time management in their projects and programs. Therefore, project and program professionals involved in developing and using schedules for management purposes often are not qualified and do not have the necessary knowledge, skills, and expertise to make adequate use of schedule models to support management decisions aimed at making projects and programs to deliver the scope and benefits on time.

Despite this scenario, scheduling is at the birth of Project Management as a management discipline in its own right. Meeting challenging and important time objectives was at the cradle for the development of Project Management back in the 20s with the emergence of the Gannt Chart, and later in the 50s with the project network diagrams, based on computer power, in particular, the Precedence Diagramming Method and the Critical Path Analysis. These time-management tools and techniques provided the basis for project management to develop as management disciplined grounded on scientific principles. Nowadays, any software tool or system that claims to support project management has as its core a scheduling engine supporting various schedule analysis functionalities, ranging from simple critical path analysis, resource leveling, down to advanced Monte Carlo simulation for risk analysis. Yet, the benefit of all these powerful functionalities rests on the validity and quality of properly developed and maintained schedules. And this can only be achieved by equipping stakeholders with the required understanding, knowledge, and expertise about the scheduling discipline. For effective time-management in projects and programs, the adequate level of knowledge of scheduling, or “time mathematics”, must exist at the various organizational levels and must not be confined to scheduling experts working in isolation from the stakeholders who make decisions and form those who execute the project work.

While high-quality schedules developed upfront in projects and programs offer a realistic baseline for managing time objectives, changes and emerging adverse conditions will always threaten these objectives and will generate delays. Being able to properly diagnose the causes of these delays, during and after the project, to devise effective recovery solutions, allocate in a balanced, auditable and transparent manner responsibility amongst the various parties, and to develop valuable lessons learned for the future, is a major goal and benefit of the scheduling discipline.

Proper scheduling requires the consideration of various elements of effective time-management, namely: activity and schedule duration estimation, integration with scope definition and management, establishing activities’ progress criteria, using internal and external dependencies, integration with resource estimation and management, integration with cost estimation and management, integration with risk analysis and management, and integration with communications management, performance reporting and performance management ultimately sustaining Earned Value Management implementation.