Here’s a safe assumption: Email is one of your key employee communication channels.

There’s nothing wrong with that, unless you’re not using email as effectively as you could be.

For example, several organizations I know send a push news email out late in the day (after 2 p.m.). Yet many email experts believe that email open rates are higher first thing in the morning.

These experts tend to focus on external email marketing, so it’s possible that your employees’ habits are different. But unless you know for sure, you could be undermining your efforts by sending email at a time when employees are too busy or distracted to open it.

And speaking of email, how compelling are your subject lines? The subject line is the second factor that determines whether people open an email (the first is who sent it), yet many subject lines I see are dull and irrelevant.

That’s why you should read this post from Email Critic’s Dayne Shuda about the five ways to make subject lines interesting.

Email Critic’s first piece of advice is to use urgency in your subject line. “Urgency is a big emotional driver,” Mr. Shuda writes. “People respond when time is running out.”

Even more essential is to offer something valuable to employees. “You don’t need to get tricky or cute with the subject line if your [content is] on point. Simply tell the subscriber what they want to hear. Help them in some way and you’ll earn their attention.”

A third way to make your email subject line interesting is with a call to action. It’s this simple: “People respond when you ask them (or tell them) to do something.”

Email is obviously an essential communication tool, but it’s hardly foolproof. The more you learn about the art and science of email, the better you can use this tool to effectively reach employees.