People can find out how to sign their pooch up to be the next Scooby Doo tomorrow.
Under Hertsmere's Dog Watch scheme, people are encouraged to report any suspicious activity they see or hear when walking their four-legged friends.
PCSO Marie Harvey is encouraging dog walkers to back the scheme to help police sniff out crime and anti-social behaviour.
She said: “Dog walkers spend a lot of time out in their communities and would know if something suspicious or out of the ordinary was happening in their neighbourhood.
“Dog walkers can not only help cut crime but can deter offenders.”
During the event, people will also be able to get their hands on free pesonal safety items including Dalmatian-styled attack alarms and UV security marking pens.
The day, organised by Hertsmere Community Safety Partnership, will be held at Kenilworth Park, Borehamwood, from 11am to 2pm tomorrow.