The Shop, Distributive and Allied Employees' Association (SDA) is a private sector trade union in Australia, representing retail, fast-food and warehousing workers,[2] and has branches in each state and territory.

During the 1890s and the early 1900s, the predecessors of the SDA first came into existence in most states, particularly through 'Early Closing Associations' focused on restricting shop trading hours.

[7] In 1987, the SDA helped facilitate compulsory employer payments of 3% superannuation for employees paid into industry fund REST Super with joint union-employer directors.

[7] In 1991, the Australian Hairdressers, Wigmakers and Hairworkers Employees' Federation and the Mannequins' & Models' Guild of Australia merged with the SDA.

It was the biggest financial contributor to unions in the 1998 Australian waterfront dispute and the 'Your Rights At Work' campaign, which is credited with overturning John Howard's WorkChoices laws.

[10] It continues this tradition today through its contribution to the ACTU's Change The Rules campaign focused on reforming Australian industrial relations in the lead up to the 2019 federal election.

De Bruyn remained the SDA's honorary National President until he was replaced by Victorian Branch Secretary Michael Donovan 2018.

The SDA brought Solidarity on tour to Australia to pressure the repressive, communist Polish Government as well as financially support charities that assisted Poland in its transition from communism.

In response, the SDA established a hotline and dedicated team of industrial officers to help workers recover lost wages.

[17] In 2017, the SDA launched a national public awareness campaign "No One Deserves a Serve" to combat what the union described as the growing problem of violence and abuse directed at retail workers by customers.

Following this decision, some media outlets criticised the union for poor outcomes in its workplace negotiations due to the union bargaining for industry-wide conditions with a result of beneath-award pay outcomes for members, despite the newly applied test not taking into account above Award conditions including Annual Leave Loading.

[29] The Sydney Morning Herald claimed that a quarter of a million workers across several major employers had been underpaid as a result of the union's negotiations, labelling it a "national wages scandal".

[31] One controversial aspect of this has been the widely used practice across many industries of paying an administration charge for payroll deduction of union dues from major companies.

[34] The union has been a leading supporter of many significant Labor Party reforms including Medicare, Compulsory Superannuation and abolishing John Howard's WorkChoices laws.

Present federal members of Australia's parliamentary Labor Party that have a close association with the SDA include House of Representatives members Tony Burke, Nick Champion and Amanda Rishworth and Senators Catryna Bilyk, Raff Ciccone, Don Farrell, Deborah O'Neill and Helen Polley.

[40] Prior to this, several SDA-aligned Labor MPs expressed public support for same-sex marriage in opposition to the SDA leadership including Kate Ellis, Amanda Rishworth and Nick Champion.