The origins of this Union can be traced back to a trades union known as the Association of Women Clerks & Secretaries or ASWCS which had a specialised branch specifically for school secretaries. In the 1940s, the ASWCS merged with the National Union of Clerks, the school secretaries became unhappy with this new body and in 1951 they broke away and formed their own School Secretaries' Association or SSA.
The SSA changed its name to the National Association of Administrative Staff in Schools and Colleges or NAASSC in 1995 in order to widen its remit to include all administrative staff employed in education. Since 2001 it has been affiliated to the Professional Association of Teachers or more specifically the its Professionals Allied to Teaching or PaTt wing.