One of the main areas of the Project Management Body of Knowledge deals with stakeholder identification and analysis. While this is mostly thought of as a PM task it is very important for Business Analysts to know and understand the stakeholders in a project as they go through each of the phases of the project. A BA is going to be interacting with many different types of stakeholders and it is important for them to analyze how best to reach out to them for information as well as elicit the needed requirements to complete their work.
The first step is to understand what the roles of the different stakeholders are. Are they the project sponsors? Are they end users? Will they not be a user of the finished product, but they do have a vested interest in how the project turns out? Are they a SME in a certain area that you will need to go to often for knowledge and expertise? Remember that a stakeholder is anyone who can influence or is influenced by your project. Know the attitude and influence of each of the stakeholders. What is their attitude not only to the proposed solution, but also to you. Do they see you as a "hired gun" brought in to shake things up? Do they see you as someone creating something that will eventually put them out of a job? Or do they see you as an expert in a field brought in to solve a problem. There is almost always some office politics around a project or decision so it is important to know who all the players are so you can avoid the politics as much as possible, but also use them to your advantage when needed.
I attended a Gartner Local Briefing recently in which the presenter talked about the different types of stakeholders in a project. Of course there are the owners, deciders, doers, and consumers. However, there also can be waiters, watchers, talkers, and the sporadic expert. As you go about gathering requirements and designing the system it is important to know the needs of each of these people, their importance to your goals, and how they should be engaged. Show compassion to those you are interacting with, especially those who could be impacted largely by the project. Compassion is not only a nice people skill to have, it can be help you to create relationships with those stakeholders that you will be interacting with. More than likely there will need to be multiple interactions with stakeholders throughout a project and having those established relationships will make things easier.
As stakeholders are defined in a project it is the job of the Business Analysis to evaluate the impact each person could have on their efforts. Understanding this up-front will help to shape the effort and ensure a higher level of interaction.