Leads and Lags in Project Management

As a Project Manager, you have to understand Leads and Lags concepts to make Project Schedule diagram and also necessary to keep track of activity duration.

Lets understand that:

Leads:

Generally, Second activity starts when first activity finish, but some time the scenario is different like two activities can be processed parallely. For example, second acitivity can be started after few days of first activity finished. If you want to start editing photographs of Photo session of 4 days schedule then its not necessary to wait till 4 days to finish full session and then start editing, on the other hand photo editing can be started after 1 day of photo session and both activities can be proceed in parallely way.

Lets say activity A duration is 5 days and activity B duration is 3 days. Activity B can be started after 3 days of Activity A is started then 2 days are called Lead here. Its called Finish to Start with 2 days lead, means Activity b can be started after 3 days of activity A finished. Lead can be used only in Finish to start activity relationship.

Lags:

Lag is when successor activity is delayed that much amount of time due to predecessor activity. Lets say Activity B can be started after 3 days of Activity A finished then 3 days are called Lag in this scenario.

Lets say, after photo shoot session, printing of photo will have to start but before that photo will be sent to customer for proof. So after 10 days of lag we can start the photo printing when we get customer approval.