What PM should do when there are multiple critical paths in a project?

When there are multiple crticle paths in a project, it means, the project has been divided into multiple phases. Project manager should ensure timely completion of multiple critical paths in order to complete the project on time..

This is where a Forensic Schedule Analyst should step in analyzing the schedule, calculate schedule Drag and provide PM a good schedule with single (longest) critical path. Or satisfy the PM with the multiple paths as sometimes there is more than one critical path like we have a project of construction of12 buildings in the different locations of the city as one project with duration of satisfying one building construction only, here we have12 critical paths but the longest should still one.

I suggest splitting the project into multiple ones to maintain no more than one critical pathe per project. If this is not doable, get an assistance project manager for each critical path.

This will be highlighted in the scoping workshop where critical items that could make it fail are put up as risks and what contingencies will be in place to avoid slipping critical deadlines.

This will further be elaborated on when in the Planning Phase (procedures, work practices & policies) and how it will be managed in Execution Phase (meetings, inspection, status reports etc.), who is responsible for it (RASCI, Organogram and communication strategy) and keeping project planner in the loop.

Every project should have one critical path only other hand the time table designer should redo the time schedule to have only one critical path to have some floating bars.

i agree with Mohammad Tohamy. 

he will accept that for there is so many time we face that matter , i think no problem ,but it need mor concentration on activity  on critical path where is the float is zero

He must put the following issues in his consideration

1.risk analysis for each path

2 . priority matrix for each path.

3.nature of each path

Then filtration and prioritization must be done for all these paths

He must pay more attention and control to all activities  on all critical paths to ensure all activities on any critical path finished on time