Update: Lots of opinions here. I posted this question to a few startup FB groups. Here are some of the answers I got from founder CEOs in those groups:<p>- CEO of an NYC startup: "We certainly don't have a summer Friday policy, but I'd say in general I don't love Friday afternoons. People definitely leave pretty early. We had to move our meetings back to the afternoons." [I assume he's saying they did that to keep employees from leaving]<p>- European startup founder: "Same thing at publishing companies in London, more or less all year long. I'm not sure why there's those policies in the media space. I'm not planning on setting up anything like that… we're not a billion dollar company yet"<p>- Startup founder: "Yeah if you do summer Fridays are for banks, big cos, you know the place where people take this for granted... do not recruit people who want this."<p>- Startup founder: "As an east coast company we don't do that, but there certainly is an expectation to take more vacations and have more flexibility during the summer months. The main and obvious difference here versus the west coast is that you guys have nice weather year round"<p>- Startup CTO: "[At my last large media company gig we] had Summer Fridays but you'd visit the office at 5pm on Fridays and we'd usually all be there. To me, it's like the startups that have no vacation policy ("if you want to go, go"). Trust your employees. If you hired right, they'll appreciate the gesture but only take you up on it when it makes sense. That said, when people do use it, I think the 'Summer Fridays' don't guarantee there are post-work events (people could get an early start on skipping town)."<p>- Startup accelerator founder: "This is not some new phenomenon; This has been going on with startups for many years - even pre dotcom. Work always happens at these post work events and people take time to recharge - if you hired right, you need not worry, as people with shit to do stay and do it, and others get more efficient, if even for a short while. It is also a great time to recruit folks and I know I have seen a lot of folks hiring recently."