Generally stated, a condo conversion is a process of entitling an income property or other lands currently held under one title to convert from sole ownership of the entire property (which often already is a multi unit property) into individual for sale units. Such entitlement is generally derived from approvals granted by state/provincial and/or local municipal authorities (and often other relevant agencies, such as conservation authorities).
http://en.wikipedia.org/wiki/Condo_conversion