People engaged in industrial action such as strikes will often adopt short and snappy slogans to make their point. This can help communicate a case effectively in situations such as media reports that require soundbites, or on placards that may be seen by passing motorists and thus must be short. Depending on your point of view, a strike slogan may be a clever way to make an argument or an oversimplification of a complicated situation.
An injury to one is an injury to all
This phrase was originally "An injury to one is the concern of all" but was altered when adopted by the Industrial Workers of the World. The term received extra attention in 2002 with the release of a film of the same title that covered the murder of an IWW leader.
One out, all out
This slogan is designed to reinforce the idea that union members stick together. The idea is that workers will strike in support of colleagues they feel have been wronged, even if they are not personally affected. The use of the slogan has become somewhat limited in the UK because of bans on secondary picketing, meaning that strikers can only protest at their own workplace and not at other facilities run by their employer.
Workers of the world, unite!
This is a shortened version of a phrase that ends "You have nothing to lose but your chains!" It is a translation of part of the Communist Manifesto of Karl Marx and Friedrich Engels. It is not a literal translation: that would be closer to "The proletarians have nothing to lose but their chains. They have a world to win. Working men of all countries, unite!"
What do we want...
This is a rhetorical device used by some protestors and would usually be followed by a short summary of their demands (such as "three percent" for a payrise) followed by "When do we want it?" and, inevitably, "Now!" The phrase was used as the title of a 2008 short film about protesting. The phrase is so popular it has been adapted into jokes such as "What do we want!? More research into a cure for ADHD! When do we want it!? Let's play swingball!" which was voted the best joke at the 2012 Edinburgh festival.
Not a penny off the pay, not a minute on the day
This was used in the 1920s when a series of strikes in individual British industries turned into a general strike of workers from all forms of trade union. The slogan conveys that the stikers were not willing to accept either a cut in wages or an extension on working hours. It has been credited to AJ Cook, the leader of the mining union at the time.