The Information Commissioner's Office has published a new code of practice designed to help firms and public bodies safely share personal data.
The ICO's data sharing code of practice covers both routine and one-off instances of data sharing. It addresses scenarios such as local authorities sharing information with the health service or building societies providing information to credit reference agencies.
The code gives advice on when and how personal information can be shared as well as how to keep it secure.
The ICO consulted on a draft code last October. It says a number of changes and improvements have been made since then, including the addition of more public and private sector case studies to explain practically how the Data Protection Act applies to data sharing.
Along with the full code of practice, the ICO has also published a summary checklist that can be used as a quick reference guide to sharing information.
Information Commissioner Christopher Graham said: "The public rightly want to remain in control of who is using their information and why, and they need to feel confident that it is being kept safe.
"I'd encourage all businesses and public bodies that share personal data to get to grips with the code without delay so they can be sure they are getting it right."
From later this month, UK-based organisations running websites in the UK will have to get "informed consent" from visitors to their websites before storing information on users' computers and retrieving it. Using cookie technology is a common method of storing this information.