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Scheduling Best Practices

In a continuing series of articles on specific aspects of critical path method (CPM) scheduling, Warner examines various facets of the process of preparing, analyzing and utilizing schedules in project management. Warner has worked in all areas of the construction process with owners, contractors and suppliers on all types of projects from residential to power plants. Through this experience, we have accumulated a reservoir of knowledge. This series of articles is designed to pass along observations and insights, highlighting best practices. The tenth article in the Scheduling Best Practices series is “Relationship Types, Lags and Leads, and How to Use Them”. Marco Ferrante, Managing Consultant in Warner’s Scheduling Group, is a recognized expert in scheduling and scheduling best practices. Marco Ferrante has over 12 years of experience in the Construction and Information Technology field serving Federal and State Government and Commercial industry. He has applied Project Management skills as a Mission Analyst to deliver an integrated Master Schedule for the largest Intelligent Transportation project in the world. Mark Anderson, Executive Vice President and Chief Operating Officer Relationship Types, Lags and Leads, and How to Use Them by Marco Ferrante, P.S.P, Managing Consultant Construction scheduling is intended to give us an understanding of when activities are to start and finish so crews, materials, and equipment can be effectively managed to complete a project on time and on budget. Schedule logic indicates which activity or activities must be completed before another or others can start. Originally, Critical Path Method (CPM) schedules (Activity on Node (AON) and Activity on Arrow (AOA)) had only Finish-to-Start (FS) relationships. Construction scheduling software manufacturers responded to the need for flexibility in activity

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