At the center of any Vista system is the golden pair : one medical professional and one programmer, working together. The medical professional knows what the software needs to do. The programmer knows how to get the software to do it. This golden pair forms the heart of the Vista lifecycle.

The further away you get from this model—one clinician and one programmer working together—the more the software will suffer. Allow your golden pairs to work together and communicate freely!

According to research done by the Standish Group, the majority of IT projects fail—that is, they do not deliver what they set out to deliver.

There are any number of reasons for this, but one very important reason is project size. Large projects are more likely to fail. Small projects are less likely to fail. Success with Vista means keeping projects to a manageable size.

Keep in mind that, just because you can state a project as a simple declarative sentence, that doesn’t mean it will actually be easy to do. For example, “all we need to do to form a lasting peace in the Middle East is to write a treaty that everybody can agree to.” Piece of cake!

If your programmers are telling you that a project is bigger than you seem to think it is, believe them.

Bugs happen. Bugs happen because software is written by human beings, and human beings are imperfect. There is no amount of pre-planning, experience, know-how, or testing that will completely eliminate bugs.

So don’t try.

Vista is designed for rapid prototyping. Get something in front of the user, quickly, rather than dragging out the process by trying to prevent what is not preventable. It is far easier to fix bugs than prevent them—so long as the rapid-prototyping model stays in place.

In everyday language, a “patch” is something you use to fix something that’s been damaged. You patch a threadbare jacket, or a leaking tire, or a software vulnerability.

In Vista, the term “patch” began with that meaning, but soon expanded. Programmers found that the patching system was also the best way to distribute improvements and new features to the code. When installed as a patch, the new features do not require the Vista system to be taken offline, and the clinicians like that part.

So, a “patch” in Vista could contain bug fixes. Or, it could contain some nifty new features your users would really like. Or, it could contain both. You will not know until you look at it.

Vista patches are distributed fairly often. It is very important that your system remain patched and up-to-date. Why? Because catching up is very difficult.

Patching Vista is not like installing updates for other software. Each Vista patch triggers changes that ripple through the software. Each patch must be installed, one at a time, with no skipping.

When making soup from scratch, a chef adds each ingredient in a specified order and allows it to simmer for a certain amount of time at each step. This is important, so that the meat, vegetables, and other ingredients are neither overcooked nor undercooked, and so the flavor of the spices can come out.

Like soup ingredients, Vista patches have to be added in the right order at the right time. You cannot expect to add a bunch all at once, any more than you can expect to dump all the ingredients into the soup pot at the last minute.