What is the first step for SOA implementation?

An SOA environment is composed of several elements (tools, policies, procedures and guidelines).

When you start planning your SOA initiative you face issues relating to these elements. Then you must make a choice: will you address all the issues on a single project or will you choose a phased approach?

Addressing all the issues on a single project is a very ambitious approach. You will have to convince stakeholders to support the entire initiative at once.

If you choose a phased approach you can start by selecting just some SOA components. Choose components which surely have a high ROI. The stakeholders must recognize the value added by these components.

Evaluate your environment and identify problems that could be solved with the adoption of some SOA elements.

For example, if you have several web services being developed without any control, selecting a registry/repository is a good choice for starting the SOA implementation.

You will gradually build your SOA environment and showing the gains at each step.