The best way to engage with new people is not by cold calling or by "networking" with strangers at cocktail parties, but by working with the people you already know. Of the many types of professional relationships, among the most important are your close allies. Most professionals maintain five to 10 active alliances. What makes a relationship an alliance? First, an ally is someone you consult regularly for advice. Second, you proactively share and collaborate on opportunities together. You keep your antennae attuned to an ally's interests, and when it makes sense to pursue something jointly, you do. Third, you talk up an ally. You promote his or her brand. Finally, when an ally runs into conflict, you defend him and stand up for his reputation, and he does the same for you. An alliance is always an exchange, but not a transactional one. A transactional relationship is when your accountant files your tax returns and you pay him for his time.
An alliance is when a co-worker needs last-minute help on Sunday night preparing for a Monday morning presentation, and even though you're busy, you agree to go over to his house and help.
Reid Hoffman, The Start-Up of You