Before launching a well-intended trillion-dollar effort to revolutionize the state of the art in sales order entry, we must stop and consider the constraints that will be imposed on the solution. We'll define a constraint as
Each constraint has the potential to severely restrict our ability to deliver a solution as we envision it. Therefore, each constraint must be carefully considered as part of the planning process, and many may even cause us to reconsider the technological approach we initially imagined.
A variety of sources of constraints must be considered. These include schedule, return on investment, budget for labor and equipment, environmental issues, operating systems, databases, hosts and client systems, technical issues, political issues within the organization, purchased software, company policies and procedures, choices of tools and languages, personnel or other resource constraints, and a host of other considerations. These constraints may be given to us before we even begin ("No new hardware"), or we may have to actively elicit them.
As an aid to elicitation , it would be helpful to know what kinds of things we should be looking for. Table 5-4 lists potential sources of system constraints. Asking the questions listed in the table should elicit the majority of the constraints that will affect your solution. It will probably also be helpful to identify the rationale for the constraint, both to make sure that you understand the perspective of the constraint and so that you can recognize when and if the constraint might no longer apply to your solution. The less constrained the solution, the better.
Once identified, some of these constraints will become requirements for the new system ("use the Materials Requirements Planning system provided via our current accounting system vendor"). Other constraints will affect resources, implementation plans, and project plans. It is the problem solver's responsibility to understand the potential sources of constraints for each specific application environment and to determine the impact of each constraint on the potential solution spaces.
Returning to our example, Table 5-5 summarizes the sources and constraints imposed on the new sales order system.
Table 5-4. Potential Sources of System Constraints
Table 5-5. Sources of Constraints and Their Rationale for Sales Order Entry System