Building a network with staying power is essential in any career. When you are able to establish trust among a large contingent of professionals, their faith in you becomes a secret weapon in your arsenal, increasing your odds of success.

Knowing you've assembled a solid network of people that you can count on to bring value to each other will make you feel more confident and relaxed as you advance in your career. Of course, the connections you make won't matter if their only purpose is to serve your short-term needs on initiatives that are "now or never."

The most valuable connections will be there for you -- and you'll be there for them -- throughout your entire career.

Today's Connections, Tomorrow's Partners

I've worked with several entrepreneurs over the years who thought they had a book of professional connections. Yet, after some time had passed, they found they couldn't gain access to the individuals they most wanted to reach when they had a legitimate reason to.

If you don't reach out periodically, you'll lose those valuable resources. This is why I strive to maintain contact -- and it's helped me time and again. Staying in touch with my Apple alum colleagues, for example, has led to many opportunities for me to collaborate on some terrific projects with amazing people. I might have missed those chances if I didn't actively stay in touch and continue to provide value to them in turn.

Once you've begun networking at various industry events relevant to your target market (something all entrepreneurs should be doing regularly!), there are some key things to remember to keep your network active, engaged, and expanding:

1. Look for ways to add value to those in your network.

When I booked Jerry Seinfeld to perform for Cisco employees at Cisco's CEO John Chambers' direct request, for instance, Seinfeld subsequently asked me to arrange a meeting with him and Steve Jobs.

That was a great meeting; because he was so impressed with my ability to book Seinfeld, I established rapport with Chambers. When I ran into him years later at a restaurant, I reminded him of that connection. He was really warm and friendly and encouraged me to keep in touch with him to explore other possible opportunities.

Nothing demonstrates your respect for people more than sharing some influential connections of your own or information that may be relevant and valuable to them. Besides reinforcing the bonds of your relationship, it causes them to view you as a trusted peer, and it often engenders a desire to reciprocate over time -- though that shouldn't be your motivation for doing so.

Something else you can do to add value and maintain connections is share relevant content. If you stumble upon a timely article covering exciting news about a colleague's industry or passion, send it to him or her. Those simple gestures are uncommon and appreciated.

2. Demonstrate that you care to maintain relationships.

After you've made contact with someone and had a conversation of substance and relevance -- no matter how brief -- take fast action and follow up promptly while you're still fresh in their minds. If you don't, you run the risk of being quickly forgotten, diminishing the benefits of meeting in the first place.

Reach out occasionally to have substantive, meaningful conversations (whether by phone, electronically, or over lunch or coffee) with the people who matter to you most within your network. Find out what's happening in their lives and work so you can stay in touch with important things going on for them and seek to add value, reinforcing your relationship.

3. Establish a system for reaching out with praise.

When you hear about something great that has happened for people in your network, reach out and acknowledge their success and achievement. It doesn't take much time, but it fosters goodwill, and everyone appreciates that simple gesture.

If you don't have a system for keeping in touch with those in your network on a regular basis, it's highly likely that you will be forgotten or overlooked. Create a system that works for you and stay in contact. The key is to follow up and be genuinely curious about and interested in the other person's world.

4. Extend invites to exclusive events.

Invite select members of your network to participate in key events you're aware of that may interest or benefit them in some way.

I'm frequently involved with elite, invite-only events that aren't advertised, so when I reach out to individuals in my network and extend an invite, my colleagues are thrilled and honored that I thought to include them, even if they're not able to attend.

Even if you aren't in a position to extend invites to exclusive events, just letting those in your network know that you saw an event that they might be interested in will let them know that they are top of mind for you.

It can't be overstated enough how important it is to build your network and strengthen those relationships over time. Through your trusted connections, you can engage advisors and other specialized experts who can shore up your team in areas where it lacks the right expertise, talent, or access to influencers and clients who are key to accelerating its credibility, traction and growth relative to its target market.

What comes around goes around. Always make sure to add value.