• Load vs Capacity - It is critical for production to have a clear picture of load vs capacity for each work center in production.  Having access to this information well in advance will allow production to adjust schedules and capacities before it becomes an issues and delays deliveries.
• Infinite vs Finite Capacity - Finite capacity planning systems will level the load for each work center and push out less important jobs.  This makes it easy to see when all current jobs will be completed given current capacity constraints.  However, it can make it difficult to identify when work centers will exceed capacity thus allowing managers to adjust capacity and increase throughput as needed.  Infinite capacity planning systems do not level the load and push out deliveries.  This will clearly identify when a work center will reach or exceed capacity and allow for adjustments as needed.  However, this method does not make it easy to identify when all current jobs will be completed without changes to current capacity unless the schedules are manually adjusted.
• Common Work Centers and Activities - It stands to reason that work centers and activities that are used more often and across more jobs are more likely to be the source of a bottle neck.  This is typically a great place to start looking for bottlenecks and working to streamline the process.
• Material Availability - Depending on the type of component and the number of times it is placed on an assembly, material shortages can have as great or greater impact on on-time performance than capacity and load.  It is important to have visibility of all parts needed for each work center and whether you currently have or will have enough on-hand in time to complete the job for any work center as scheduled.  If critical components are missing, then production may need to reset priorities and schedules.

• Customer Importance - It is common for CMs to push jobs important to customers or for large customers.  While this may satisfy the customer, it is very likely to decrease overall on-time performance and establish a precedence the customer will want to repeat.  That isn't to say it should never happen.  However, it should be used sparingly and after proper consideration.  If the other methods are used properly scheduling will become less of an issue and even the large customers should be able to get their orders on-time without hurting all other jobs, customers, and performance.
• Material Availability - This method will reduce the priority for any job without sufficient material on-hand to complete the job.  Since some components are too difficult and/or time consuming to place late in the process, these parts can and should affect when a job is sent through each step in the process.  However, many components can be placed later without significant impact to schedule or processing time required.  Therefore, it is important to identify which components should and should not impact scheduling if they are missing.
• WO Due Date - Setting schedules based on due date is one of the simplest methods of scheduling.  It requires little effort to maintain and each Work Center will have the priorities set automatically.  However, for this method to allow for the highest possible on-time performance sales needs to confirm that sufficient capacity and lead-time are built in to the order before placing it in the queue.  If the load is near capacity or the customer doesn't allow enough lead time, this method is inadequate for completing all jobs on time.
• WC Bottle Necks - Identifying the Work Centers with the highest load and increasing the priorities on all jobs that must pass through that Work Center can increase throughput without increasing capacity.  For example, if ICT is the largest bottle neck and only 1/3 of the jobs need ICT, then those jobs should have a higher priority in all prior Work Centers.  This will ensure they have as much time as possible to pass through ICT and that ICT is always at capacity without down time.  Although this will not guarantee that all jobs will ship on time, it should increase the likelihood.
• Job Slack Time - The difference between the processing time required to compete a job and the available work hours until a job is complete can be called a job's slack time.  Using this method will increase a job's priority as the time required approaches the time remaining.  This is a dynamic method that may increase and decrease a job's priority as it moves between work centers based on the performance of each work center.  This also means that a job with less slack time, but later due date may get a higher priority.  For example, a job with 3 days of actual processing time required and 7 work days until it is due will have a lower priority than a job with 10 days of actual processing required and 12 work days until it is due.  This method will help ensure the highest possible on-time performance, but requires that processing and available work times are setup accurately and completely.

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