Legal Question in Landlord & Tenant Law in Massachusetts

Without reading the lease, no one can provide a complete answer. If you moved in a room-mate you should get your landlord's permission. Most leases limit occupants to those listed on the lease. Having a friend visit for a week is probably OK, a room-mate is not,

If you moved someone in your place to occupy the apartment in your place, you have to get the landlord's permission. However, without reading a lease, this answer cannot be completely accurate.

Landlord should be reasonable in granting permission, such as if you are moving in your fiance he needs to be reasonable in granting permission. However, if you are moving three people into a one bedroom apartment the landlord has every right to say no.