Maintaining clean and accurate data is one of the most important things you can do to help your organization get the most out of Salesforce.  With the Spring 15 release, Salesforce has made managing duplicates even easier by leveraging the Data.com technology, and providing a duplicate management tool to its clients for FREE….that’s right, you do not need to purchase Data.com or have Data.com licenses to use this feature. Now you can control whether and when you allow users to create duplicate records inside Salesforce, customize the logic that’s used to identify duplicates, and create reports on the duplicates you allow users to create. We have so many clients paying for 3rd party apps to do all of this….pay no more! 

Setup of the Duplicate Management feature is quite simple.  The first step is to create duplicate rules to define what happens when a user tries to save a duplicate record.  You can alert the user to the potential duplicate, and even block them from creating the record:

Then, you create matching rules to determine how two records are compared and identified as duplicates (or even better, activate the standard ones that Salesforce provides):

Once the rules have been activated you can report on records that were flagged as duplicates to see how well the rules are working and fine tune them as needed.

Click here for the full article on the setup of the Duplicate Management feature: Salesforce Duplicate Management