1. A method, comprising: receiving from a first tenant an indication of permission to share a portion of first tenant information with a second tenant, the first tenant information managed using a multi-tenant on-demand database service, wherein the second tenant is otherwise blocked from accessing the portion of first tenant information absent the indication of permission; permitting the second tenant to access the portion of first tenant information based on the indication of permission, utilizing a processor; receiving from the second tenant another indication of permission to share a portion of information of the second tenant with the first tenant, wherein the first tenant is otherwise blocked from accessing the portion of the information of the second tenant absent the other indication of permission; and permitting the first tenant to access the portion of the information of the second tenant based on the other indication of permission, to provide reciprocity of sharing of tenant information between the first tenant and the second tenant; wherein the indication of permission is received from the first tenant via a graphical user interface of the multi-tenant on-demand database service; wherein, after receiving the indication of permission, the graphical user interface allows the first tenant to subsequently block the second tenant from accessing the portion of first tenant information.