updated: June 25th:

CHECK-IN ADVICE for Amsterdam Airport Schiphol (due to the holiday season) and valid from June 27th till July 28th 2008:

As a result of the summer holiday season, KLM passengers departing Amsterdam Airport Schiphol may experience additional queues in clearing the passport control and security checks.

We strongly recommend that you allow extra time during weekends (Friday, Saturday, Sunday and Monday) for check-in, passport control and security checks. We therefore advise you to be at Schiphol airport at least three hours before the departure time of your flight . 
To avoid long waiting times at the regular check-in counters, we advise you to use the Self Service check-in facilities,or use the internet check-in and use the drop-off points for your baggage.

Start your journey relaxed and take your time !. 

For actual information about arrivals/departures of KLM flights and partner airlines, Click here
 

Important security information
Extra security measures for hand baggage on all airports in the EU. Click here. 
For a comprehensive list of exceptions, click here.