For any well-done information management project, there exists a set of documentation.

I've recently come into many shops to help clients overcome process, organizational and technical challenges and many times documentation is non-existent.  Of course, we all know many benefits of good documentation but also know that it helps consultants be a quick-study and get straight to advice or action.

But what documentation is necessary and is it necessary if you are deploying an agile methodology?  I'll answer the first part below but my answer to documentation and agile is that yes, documentation is important in agile.  If you are going to support the system, potentially do something similar again, hire consultants or have employee turnover, you need documentation - at the appropriate times and with appropriate, not necessarily excruciating, detail. 

You also probably do not want to be the person who repeats himself repeatedly, which is what you'll do without documentation available to hand out.  Repeating oneself is hardly the most advanced use of time.

The documentation can be built with agility just like the systems, but here is a list to think about delivering (or, as the case may be, retrofitting).  It's a STARTER list for what is necessary.

• Non Functional Requirements - Describes the environment in which the system operates
• Decisions Capture - A place to catch all those important decisions that are made and a vehicle for making those decisions visible in the culture
• Logical Data Model - The logical data model should not exist without narrative
• Test Approach - Describe how the development will be tested - systems, data, user involvement, players, etc.
• Interface Specification - Interfaces are largely what these projects are all about - either interfacing existing systems or adding multiple components that need interfacing themselves
• Startup Plan - Day 1 of production is hardly when data can begin accruing in new information management projects; Planning for and loading the data backlog needs a plan
• Data Access Specification - Describes how the new data being made available will be accessed by users and systems

Do yourself a favor.  Inventory your documentation set and make sure it's the right level for sustaining the system.