Take Control of Duplicates—Use Duplicate Rules and the Potential Duplicates Component

Duplicate rules are your control panel for maintaining good clean data. If your org was created in Spring ’15 or later, standard duplicate rules came activated for you. To alert sales reps to duplicates of records they view, add the Potential Duplicates component to your layouts. Configure a duplicate rule to warn sales reps when they’re about to create a duplicate. Or block new duplicates altogether, even on records that reps don’t have access to. Optimize a rule for any custom fields and company workflow. To learn more, check out these resources: In Salesforce Help, see
Create or Edit Duplicate Rules, https://help.salesforce.com/articleView?id=duplicate_rules_create.htm&type=5
Things to Know About Duplicate Rules https://help.salesforce.com/articleView?id=duplicate_rules_overview.htm&type=5
Help Your Users Minimize or Merge Duplicates https://help.salesforce.com/articleView?id=duplicate_rules_what_my_users_see.htm&type=5
and watch the video Use Matching Rules to Hunt Down Duplicate Records. http://salesforce.vidyard.com/watch/PdYJPLbTqiI-kCXlWrr32w
Need additional guidance? Bring your questions to an Ask the Expert webinar. Search sessions and register here: https://sfdc.co/7I4hc