Ben Groenewald joined the South African Police Service on 7 December 1967 at the age of 17. He was appointed as an officer in the police in 1975 and promoted to the rank of an Assistant Commissioner on 1 December 1998. He served in most of the functional components within the South African Police Service and is involved in Major Events Security since 1990 which include the following international sporting events:

 1995  IRB Rugby World Cup
 1996  Olympic Games Atlanta
 1998  World Athletic Championships South Africa
 2003 ICC Cricket World Cup
 2007 ICC T20 World Championships

In 2005 he was appointed as the Chairperson of an inter departmental planning committee within the Government Security Structure to coordinate Safety & Security for the 2009 FCC and 2010 Fifa World Cup.

During the period 1985 – 1990 he was the Head: Presidential Protection Unit, responsible for the Safety and Security of the State President of South Africa. 

He has a BA (Honours) Degree in Police Science.