Amsterdam is generally a very safe city, if you know how to move through it – with your eyes constantly on all sides of you and on your belongings. This general mindset will keep you safe, in terms of the myriad forms of transportation that you will surely notice zipping by you at all times of the day and night (especially the treacherous bikers and trams that might initially appear to move without rhyme or reason), as well as the potential pick-pockets, who are a known concern in any large, crowded city. Other than these broad concerns, there are hardly any serious risks that should leave you feeling seriously threatened while walking in Amsterdam, be it day or night. In any case, Amsterdam is the place where you can always find a policeman around the corner; they usually walk, bike or ride horses in pairs. Even the Red Light District, which is perceived to be “dangerous”, is a well-guarded area.
It is always wise to keep your wallet or bag close to you and in a protected area, since Amsterdam does have its fair share of grubby hands that are specifically searching for and skilled at locating those people who have forgotten to remain aware of their valuables at any given moment.