Chronology of rent and condominium control steps in Boston

Boston September 1969: First declaration of a ''housing emergency'' brings 120,000 rental units under rent control.

October 1974: Public housing and private housing that received federal subsidies are exempted from rent controls. About 35,000 rental units are exempt; 85,000 remain under rent control.

December 1975: ''Vacancy decontrol,'' which begins to return rents to the market rate, is enacted. Since then, some 60,000 rental units have been decontrolled, leaving 22,000 to 23,000 units under full rent control.

Under vacancy decontrol, a landlord is allowed to raise the rent to market rate when a tenant moves out. The next tenant is not allowed to file a grievance to protest an eviction or a rent increase unless:

* The tenant qualifies as a low-income resident ($18,000 for a single person;

* The tenant is elderly.

* The tenant is handicapped.

To appeal a rent increase, these tenants must file a grievance within 30 days after being notified of the increase. No rent protection is extended to anyone who has moved to Boston since January 1983.

December 1979: Regulations are enacted to govern eviction procedures during condominium conversion. Most tenants must receive one year's written notice. Low-income, elderly, and handicapped tenants must receive two years' notice.