It is so important for people in the business analysis role to build strong, solid relationships both in and out of the office.  Many people dislike the term "networking," but I feel it is one of the most important skills of a successful BA.  By helping others and asking for help, solid relationships are formed.  Here are two key reasons you should always be working on your network to improve both personally and professionally.

1. Knowledge and Experience: 

"No one lives long enough to learn everything they need to learn starting from scratch. To be successful, we absolutely, positively have to find people who have already paid the price to learn the things that we need to learn to achieve our goals."

-Brian Tracy, Author

You can't know and experience everything.  What you can do is be connected with people that have the knowledge and experience you need at any moment. 

2. Access and Openness:

Your assignment is priority #1 for you.  It may not be for the SME's and other stakeholders you need time from.  By having built relationships with those you work with the necessary doors will be open and time will be given.

Trust is a big part of a good relationship.  Your SME's will be more open and honest with you during a project if they trust you. 

Work on building your network…you wont be sorry.  Here is a great resource that has helped me over the years.