Which software development methodology is the best for web development ?

Interesting question really, and something posed by a customer recently.

I have to say that our own methodology has evolved over the years.  We have used most if not all of the software development process models in the time that I have been here.

We are unlike most web designers in that we are top heavy in programming staff, and we use our own software, typically Freestyler and Concord as frameworks for almost all of our projects.

When I first came on board at Datalink around 2001, we developed a lot of custom software applications for e-entrepeneurial and corporate e-business projects.  Having come from an ISP and web design background, our company became a strict proponent of the waterfall model.  The waterfall model is a sequential process with clear phases for requirements analysis, design, implementation, testing, integration and maintenance.  This model was easy to understand and implement and track for our project managers, although from time to time projects would slip due to delays in customer feedback.

After a few years, around 2004, the Extreme Programming was suggested as an option, however it was never really adopted, except for a brief time when we were low on resources. 

For one or two web application projects back in 2005, namely the Commonwealth NAS Intranet system and the Thomson Real Estate database, we used a Rapid Application Development process.

More recently, we have used iterative and incremental development models, and are tending towards the Agile model, due mainly to the rapid evolution of the web and technology.  These models promote customer feedback and re-evaluation of priorities at all stages and require maximum flexibility, customer visibility and face-to-face contact.

In many ways, we remain methodical developers, but in the Web 2.0 world, the Agile model is probably the best way for companies like ourselves to go to adapt and maintain customer satisfaction.  However there are many instances where we need to keep things in check.  For instance, dealing with government relies on accountability and the waterfall model is still relevant in this case.  In this instance, we are far from "cowboy" software developers.  So we remain selective between models and our methodology combines aspects of both.