A trio of cars were stolen without the use of keys from three different homes.
Thieves took a car from a Slave Hill driveway in Haddenham between 10pm on March 14 and 10am on March 15, police said today.
A car was then stolen from St Michaels Close in Halton between 11pm on March 16 and 7.30am on March 17 before a third car was taken from Dovecote, Haddenham, between 10.30am on March 31 and 6am on April 1.
The neighbourhood team advise drivers to consider fitting security devices and tracking systems - approved by Thatcham or Sold Secure - in their cars.
An immobiliser - which will stops the car from being driven away - should also be considered and when locking keyless cars, test the doors to make sure they are properly locked.
Anyone with information about the thefts in Halton and Haddenham should contact the Aylesbury Rural Neighbourhood Policing team station via 101.
Alternatively, contact Crimestoppers anonymously on 0800 555 111 or online at Crimestoppers-uk.org