Dynamics 2015 - Security Role: Changing ownership of a record

Hello All,

I would like for folks on our sales team to be able to change the owner of a "Lead" or "Opportunity" from one sales rep. to another.  But I am not sure which Security Role I need to change to make that happen.  They are under the "Salesperson" role now.  Would the option be under the "Sales" tap?

Thank you for your help!