Research has found that rekindling dormant professional relationships can offer tremendous career benefits to executives. But a new study shows that some reconnections are more beneficial than others — and that executives often don’t select the best reconnection choices.

Reconnecting with long-lost or dormant contacts can be very valuable — both professionally and personally. But choosing from among hundreds of former contacts can be challenging. We find that executives, when left to their own devices, don’t take full advantage of their opportunities to reconnect. And when they do reconnect, they tend to focus on comfort and not on re-connections that might offer the best advice.

As the nature of work and professional life becomes more varied, people accumulate an ever-increasing number of former colleagues and contacts. Although the Internet and social media have made it fairly easy for people to maintain their relationships, most managers find it impossible to stay in active communication with everybody. Inevitably, they lose touch with many of their former contacts. When these previously valuable relationships become dormant for several years, they can seem like they no longer exist. But unmaintained relationships are not dead at all: They can be revitalized fairly easily.

Our original study on reconnecting such dormant ties (described in our 2011 MIT Sloan Management Review article, “The Power of Reconnection — How Dormant Ties Can Surprise You”) investigated the interactions of hundreds of executives. (See “Related Research.”) We found that reconnecting with people from previous chapters of one’s life (such as former colleagues, old friends, and other associates) is as valuable, if not more so, than connecting with currently active ties. There were three main reasons behind this effect. First, it turns out that dormant ties are great sources of unexpectedly novel insights and ideas. After all, the individuals were not hibernating while you were out of touch; they were out in the world, doing and learning new things, so they can trigger new ideas that are often more valuable than the “same old, same old” from the people in your current network. Second, reconnecting is an efficient investment of time. Rather than requiring lengthy conversations, interactions with dormant ties are often relatively short, delivering good “bang for your buck” — obviously very good news for busy executives. Third, we noted that reconnecting a dormant relationship is qualitatively different from starting a relationship from scratch. Old feelings of trust and a common perspective do not fade away and are rekindled almost immediately.