Unable to restrict person security profile using agency name or ID

Summary:

Hi ,

We have a requirement where we need to build the custom person security profile which should restrict based on the agency name or id.

I can see ther IRC_Agencies contains the agency names but not sure how to join with any other table which holds the person id and agency details to restrict the persons

Please advise on the same. Inputs are highly appreciated.

Regards,

Ganesh