When a parcel of land, or existing structure or use fails to comply with current zoning bylaw or ordinance requirements, it is deemed to be "non-conforming."  Despite this fact pre-existing non-conforming lots, non-conforming structures and non-conforming uses are typically considered lawful — provided that they were lawfully in existence before the enactment or amendment of the zoning provision that made them non-conforming.  Changed to these uses or structures usually requires zoning relief.  Attorney Dowling can assist you in this sometimes complicated and confusing process.