Working hours and breaks are governed by the Arbeitszeitgesetz (Law on working hours), collective wage agreements and company agreements, or arranged on an individual basis. At present the working week varies between 38 and 40 hours. Normally the working day is not to exceed eight hours. But what’s written in paper may not represent what practically works especially in certain high-pressure jobs like consultancy or upper management where many work much longer hours without overtime allowances. A break of at least 30 minutes is mandatory after six hours' work. A rest period of at least 11 hours must be observed after a full working day. Employees cannot normally be required to work on Sundays and public holidays. There are exemptions for a large number of activities.
Flexi-time options are also popular in Germany. Over 28% of the working population opts for this where they have more flexibility in deciding what time they work.
Source
Beside paid leave, there are 5 national holidays:
More information can be found at:
http://german.about.com/library/blfkalender2.htm