We’re all overwhelmed with email, said Adam Grant. But ignoring personal email is just plain rude– it’s “digital snubbery.” And a growing body of evidence suggests that if you care about your job, your inbox should be a priority. When researchers examined the digital habits of teams at Microsoft, they found that the “clearest warning sign of an ineffective manager was being slow to answer emails.” By contrast, responding in a timely manner “shows that they are conscientious–organized, dependable, and hardworking.” Yes, we’ve all read the study showing that spending too much time on email can make you less productive. Except that applies only when email isn’t central in your job. “And let’s face it: These days email is central to most jobs.” If you have too much on your plate, come clean and say, “I don’t have the bandwidth to add this.” If you want to say no, just say “no.” You can even set up an auto reply to give people another channel to reach you, such as a Slack channel or Twitter. But whatever boundaries you set, you can’t just ignore your inbox; that’s like not answering the phone in the 1990s, or not answering letters in the 1950s. If you’re habitually too busy to reply to legitimate emails, there’s a problem. “It sends a signal that you’re disorganized– or that you just don’t care.”