Being well networked is not just something to do when looking for a job. Being well networked is critical for your long-term success within an organization too.
Unfortunately, many people get "comfortable" within their own department and role and don't take the initiative to expand their reach. In times of rapid change, this can be a huge mistake. Often times I see companies laying off people in one department and hiring people in other departments.
Being well networked is the core of the free agent. It enables you to move around an organization. Think about it. If there is another person in your organization with the same exact level of skills, experience, and knowledge, the only thing that will separate you from her is who you know.
So, start to take on additional duties. Find opportunities to volunteer that give you exposure to key leaders. Constantly look for new ways to add value that go beyond your job description.
Building your internal corporate network serves both you and the organization. It gives you more flexibility and exposure to move horizontally and vertically as your organization deals with constantly changing market conditions, and the additional value you add helps the organization achieve its strategic goals.