AUPE is primarily a public sector union, with members employed in government, health care, education, boards and agencies, municipalities, and occasionally private companies.

As of 2014, the union had a staff of more than 100 employees at its headquarters in Edmonton and seven regional offices across Alberta, including Peace River, Grande Prairie, Athabasca, Camrose, Red Deer, Calgary and Lethbridge.

In the fall of 2007, it undertook a major campaign to press for changes in Alberta's labour laws, which ban strikes by most AUPE members.

In the mid-1990s, AUPE saw its membership fall due to the privatization of some government-run services during the provincial leadership of Premier Ralph Klein.

MacLennan's efforts were aided by increasing moderation in the policies of the Klein government in the years after the cuts of the mid-1990s, as well as by rapid economic and population growth in the province of Alberta.

Doug Knight was elected president in a by-election in 2006 after MacLennan left the union to pursue a career in the private sector.

AUPE began life on March 26, 1919, when a small group of Alberta government employees held a founding meeting in north Edmonton's First Presbyterian Church.

They bargained pay and working conditions through an advisory joint council established by the United Farmers of Alberta government that same year.

While the CSA had grown enormously in size and vitality by the late 1970s, surpassing 30,000 members, its leaders recognized the need for legal recognition as a full-fledged union.

That same season, employees of the Alberta Liquor Control Board went on strike for 10 days, winning substantial wage increases.

However, PSERA had been passed over the objections of AUPE and other unions, who remembered Alberta Premier Peter Lougheed's 1971 pre-election promises of full bargaining rights for public employees.

Instead, Lougheed's government passed the most restrictive labour legislation in Canada, which included compulsory arbitration designed to favour employers.

AUPE's inception took place in 1976, the same year that Canadian Prime Minister Pierre Elliot Trudeau announced wage and price controls with an Anti-Inflation Board, making it illegal for employers to negotiate pay increases above a certain guideline.

The years 1987 to 1996 were a challenging decade for AUPE — with layoffs and privatization taking place under the provincial government led by Premier Ralph Klein.

Membership continued to decline, mainly through cuts to the government service, and AUPE faced substantial debt, reduced revenues and crippling building costs.

When bargaining stalled in 1990 and government pressed ahead with its divestment of people services, social workers in Local 006 led a 22-day strike over workload and staffing.

The result came under the planning of Premier Ralph Klein, along with Vermilion veterinarian and MLA Stephen West, a provincial cabinet minister.

Facing a deteriorating financial situation, AUPE's Executive called a special convention in July 1994 to seek a temporary dues increase to 1.5 percent.

After an extended campaign, AUPE ratified agreements containing cutbacks in the order of 2.3 percent, with the remainder taken in days off and holidays.

With massive support from other AUPE locals, unions and the Calgary public, the workers forced Premier Klein to make a concession.

AUPE flexed its collective muscles in illegal but effective job actions, and began to pick up unprecedented numbers of new members through mergers and organizing.

Other successes followed, and even though AUPE faced fines and dues suspensions for its actions in defense of its members, its financial situation began to improve.

AUPE asked Alberta residents to sign letters to their Members of the Legislative Assembly stating that they wanted the Legislature to pass new laws that would guarantee the rights of all working people to fair and full collective bargaining.

[9] The initial event that started the strike is cited by the AUPE as the indefinite suspension of two union members after they voiced concerns over health and safety issues at the Edmonton Remand Centre.

However, emails to the site's Executive Director which contained crude and disrespectful comments were the driving force for the union members' suspension.

[12] By the morning of Saturday April 27, all 10 correctional centres in Alberta (in Calgary, Edmonton, Peace River, Medicine Hat, Lethbridge & Red Deer) were all actively participating in the wildcat strike.

By Monday morning, the Edmonton area Alberta Sheriff Department had held a vote, which resulted in them joining the strike.

Sheriffs were joined by Probation Officers, Social Workers and Court Clerks as they marched outside Courthouses located in Edmonton and Calgary.

[15] Throughout the wildcat strike, the Minister of Justice and Solicitor General Jonathan Denis remained largely quiet, with most statements actually being issued by the Alberta Deputy Premier Thomas Lukaszuk.

At convention – normally held in late October in Edmonton – policies are established, budget and operating procedures determined and executive committee officers elected by a vote of delegates.