IT Success!: Towards a New Model for Information Technology

5.3. Iterative development in practice

The iterative or prototyping approach can be broken down into the following phases, which we'll explain in further detail below:

• Defining detailed requirements during workshops;

• Prioritizing business processes;

• Building a prototype;

• Validating the prototype;

• Implementing a pilot;

• Implementing subsequent releases.

5.3.1. Defining detailed requirements during workshops

As explained in the previous chapter on demand management, once an idea has become an approved and funded project, it falls out of the pipeline into the supply phase (Figure 4.1). However, since the project was approved based on high-level requirements and a high-level business case, the first step in the supply phase is to define the detailed requirements – based not on 'specifications', but on process modelling and data modelling.

Process models do two things. Firstly they explain what people do, e.g. first someone answers the phone, then takes down the customer's name and address, then enters the order. Secondly, they explain how they do each of these steps, e.g. manually, semi-manually or automatically using a particular tool or system. A process model is the fundamental starting point for any IT project since it is from here onwards that you're going to decide which parts of your work you're going to try and improve.

Data models describe the underlying relationships between the everyday things that business users work with. To take the simplest example, a customer can have more ...