The quality of the camera surveillance systems which can be bought today differs a lot. As a possessor or potential buyer it is important to get enough
knowledge to be able to specify the own security need and then prescribe functional requirements. These requirements should cover:

• visual quality – the possibility to see certain things at certain
  positions, 
• security – secure handling of the image material and system reliability and
• accessibility – fast and complete access for the police.

The Swedish National Laboratory of Forensic Science – SKL has produced three documents with advices and guidelines. The two at the top row below
have been translated into English.

• Camera surveillance – Test your system before a criminal does!
  Requirements established for four system levels.
• The Swedish police requirements for camera surveillance systems
  A handout with guidelines.

SKL - the Swedish National Laboratory of Forensic Science