TL;DR

Every project is unique, and this is defined by the project context. But how to identify your project context? You first need to set project drivers, constraints, and floats. The post is based on a remarkable book written by Johanna Rothman, Manage It!.

Every project context has three main parts:

1. Drivers
2. Constraints
3. Floats

First list customer (sponsors) project expectations. They pay the project budget, without their money, there will not be a project. Customers project expectations usually fit into the following groups:

1. Feature set
2. Delivery time
3. Quality aspects
4. Budget

Constraints are what you can not change during the project duration. For example, use the Ruby On Rails framework or use these people. You are stuck with that, and you can not change it. List all of the constraints defined by the customer.

Now it is time to set your project drivers, constraints, and floats. You start from a customer list of expectations and constraints. Pick one item from the list that will become your driver. Pick one expectation that you find the most important. This is where your job as a project manager starts. You have to make a decision. Picking the most important expectations is on you, that is what you are paid for.

Software tester alert! You could be offered to make that decision. This is NOT ON YOU!

The second decision is to pick one constraint. As a project manager, you could be forced to choose several constraints. But for successful project management, you need to manage ONE constraint.

What is left on the list are floats. Those items could be changed or juggled during the project. For example, if you left the feature set, you can change what goes into the final release.

Do not pick drivers that could not fit into constraints. It is not likely to have 1000 features with a team of two people and a budget of 1000 US$.

If you want to have a successful project, you would have ONE driver, ONE constraint that FITS with driver and FOUR floats. If the project still fails with those numbers, this would be a result of bad project management. But if with fails with four constraints, this is not on you.