The Inco strike of 1978 (locally referred to as the Sudbury Strike of 1978) was a strike by workers at Inco's operations in Sudbury, Ontario, which lasted from 15 September 1978 until 7 June 1979. It was the longest strike in Inco or Sudbury history until the strike of 2009–10, and at the time broke the record for the longest strike in Canada.^[3] It has been noted as one of the most important labour disputes in Canadian history.^[4]

The conflict was caused by proposed layoffs and cuts to pay and benefits by Inco management, with low nickel prices as a justification.^[5][6]

Around 11,600 workers were involved in the strike, which affected the wages sustaining 43,000 people, or about 26% of the population of metropolitan Sudbury.^[2] By the end of the strike, the company had been starved of over twenty-two million hours of labour, smashing records for the longest strike in both Canadian and Inco history.^[1]

Community support for the union was strong, with local politicians such as future mayor and then-Member of Parliament John Rodriguez as well as other New Democrats vocally supporting the strikers.^[7] A major role was played by women's support committees, which had also existed during the 1958 strike.^[8]

The role of women in the community during the strike was profiled in the 1980 documentary film A Wives' Tale (Une histoire de femmes).^[9]

Concessions won as a result of the strike included Inco's "thirty-and-out" policy, whereby workers with thirty years at the company could retire with a full pension, regardless of age.^[6] As well, most miners received a dollar an hour wage increase.^[1]

A study on alcohol consumption showed that over 35% of strikers and over 40% of their wives reportedly stopped drinking alcohol or drank dramatically less during the course of the strike, while a small minority drank much more, hypothesized as being stress-induced. Overall, alcohol sales declined by 10% during the strike as compared to the previous winter, likely due to economic reasons.^[2]

This effect was mirrored in the rest of the local economy, which was catastrophically affected. This would later play a critical role in spurring new economic development efforts in the city into the 1980s and 1990s; when a longer strike hit the same operations, now owned by Vale, in 2009, the action had a much more modest effect on the city's economy than the 1978 strike, with the local rate of unemployment declining slightly during the strike.^[10]

• Timeline of labour in Greater Sudbury