Summer is almost upon us. Roll out the barbeques, calm the kids, and ... begin the inevitable hand wringing about the slump in productivity at work.

Warm weather, vacation distractions, and a general easy feeling can add up to productivity declines of 20 percent, according to one study released last summer.

But must your joy be marred by concerns that your business will suffer? Can't you enjoy the summer and keep things humming at work? Rest assured that you can.

Constant work isn't the same as maximum productivity. Discipline has its limits, and flexibility its advantages.

Here's The Atlantic defending the right of the man with the toughest job in America--the president--to go on vacation:

"Breaks are better for our brains than overtime. Where you get your break -- from an hour on blogs, a day in the park, or a week golfing at Martha's Vineyard--doesn't matter so much as that you get it. If you care about your own productivity, don't be afraid to goof off online. And if you care about decision-making at the national level, tune out the critics and root for your president's golf game."

If psychological and management research shows the president is more productive with a vacation, shouldn't you go on one too?

If you shouldn't feel guilty about taking off work, you shouldn't have to plan every break with your team. With people off on holiday, "summer means you might have to tackle projects without a critical team member, or pinch-hit for a co-worker to keep the wheels turning," says Brazen Careerist. "If your organization doesn’t already have a shared vacation calendar, spearhead the effort to create one." Basics like communicating plans in advance, working ahead, and covering essential tasks should all be written down. 

One of the biggest productivity drains over the summer is all the time you spend daydreaming about being somewhere else. Rather than fight this weather-induced daydreaming, roll with it. But keep working.

"If work is starting to feel a little stale, you may be able to get a kick-start simply by changing your routine or environment. Try getting outside more during the workday (e.g., holding meetings outside or taking a walk during breaks) or working at a coffeeshop for some renewed creativity," suggests Lifehacker. Studies have shown "telecommuting helped workers increase their productivity in the summer."

Keep this in mind not just for yourself but your employees. Will forcing them to stay cooped up in the office make them feel motivated?

"Achievements trump hours spent," writes Forbes' Jacquelyn Smith. "Just because you’re in the office for the required eight hours doesn’t mean you’ve done your job." 

She has a good point: Business owners shouldn't fetishize face-time. Get out if it helps get more done. 

How do you keep productivity up over the summer?