From the 25th May 2018 there will be new data protection regulations rolled out across the EU known as the EU General Data Protection Regulation (GDPR). This marks a big change in data protection covering how individuals and organisations hold and process personal data.
If your local group holds and manages personal data (including names, postal and email addressess and phone numbers), you should take a look at the Information Commissioner's Office website to follow their guidance on GDPR to ensure you are complying to the new regulations. Below are some additional links which may also be helpful:
Information Commissioner's Office's Guide