A few years ago, Amy Balliett, CEO of a Seattle-based design and marketing firm, noticed that as the work week slogged on, her employees’ energy and productivity wilted.

“That would slump to such an extent that the same task on Monday would take double the time by Friday,” says Balliet, CEO of Killer Visual Strategies.

So she decided to squeeze the work week into four 10-hour days, with her 30 employees taking off either Friday or Monday. Now, she says, “Our team has more energy throughout the week since they have three days to recharge instead of just two.” And with less time to complete tasks, “They’re far more efficient and focused,” producing 25% more with the same-size staff.