Europeans take their vacations very seriously. They plan them weeks and months in advance.
People with or without children plan vacations around the published school holidays. People with children plan to spend time with their families, usually away somewhere, on vacation; people without children plan their vacations to avoid those people on vacation with their school-aged children.
There are official rules about the minimum number of vacation days an employee should receive (somewhere between 20 and 24 days per year for a full-time employee) and how many consecutive days an employee should be permitted to take if they make the request (about 12 days).
Thus, running projects during the summer period has to be carefully planned and orchestrated. You must consider vacation plans as soon as you return from the New Year’s break. You must ensure that no critical activities are scheduled during the Easter or summer vacation periods of July and August. This planning has advantages and disadvantages.
First, for the advantages: people have something to look forward to. Their attitude improves right before vacation. There are no big expectations that the project will accomplish massive deliveries during those periods. Everybody does it: from senior executives to hourly workers. For the disadvantages: don’t expect quick response times or to move things forward during a vacation period. Troubled projects will remain troubled. You won’t reach people by email or by phone. But, the good news is you have a long vacation period to forget all about it.