The Assistant Chief of the Defence Staff (ACDS) is a senior British military officer. There are a number of ACDS appointments and they are held by officers of two-star rank (rear admiral, air vice-marshal, or major general). They work in the Ministry of Defence.

Assistant Chief of the Defence Staff (Health)

The ACDS(H) reports to the Surgeon General.

• Surgeon Rear Admiral Lionel Jarvis (2008–2011)
• Major General Jeremy Rowan (2011–2014)
• Surgeon Rear Admiral Alasdair Walker (2014–2015)
• Major General Martin Bricknell (2015–2018)

Assistant Chief of the Defence Staff (Capability & Force Design)

• Air Vice-Marshal Graeme A. Robertson (1994–1996)
• Rear-Admiral Nigel R. Essenhigh (1996–1998)
• Major-General John P. Kiszely (1998–2001)
• Rear-Admiral Rory A.I. McLean (2001–2004)
• Rear-Admiral Timothy J.H. Laurence (2004–2007)
• Air Vice-Marshal Kevin J. Leeson (2007–2009)
• Rear-Admiral Alan D. Richards (2009–2011)
• Major-General Mark Poffley (2011–2014)
• Rear Admiral Tim Fraser (2014–2017)
• Air Vice-Marshal Richard Knighton (2017–2018)
• Major-General Robert Magowan (2018–2020)
• Rear Admiral Hugh Beard (2020-2022)
• Major-General David Eastman (2022-Present)^[1]

Assistant Chief of the Defence Staff (Military Strategy) later, Defence Engagement

• Major-General Alexander J.S. Storrie (2011–2013)
• Rear-Admiral Simon J. Ancona (2013–2017)
• Major-General Giles P. Hill (2017–2019)
• Major-General Stephen McMahon (2019-2020)
• Air Vice-Marshal Alastair P.T. Smith (2020-Present)^[2]

Assistant Chief of the Defence Staff (Intelligence Capability)

The ACDS(IC) reports to the Chief of Defence Intelligence.

• Major General Jerry Thomas (2009–2012)^[3]

Assistant Chief of the Defence Staff (Commitments)/(Operations, now Operations & Commitments)

• Rear Admiral David Brown (1980–1982)
• Air Vice-Marshal Clive Loader (2002–2004)
• Major General Nick Houghton (2004–2005)
• Major General Chris Nickols (2005–2008)
• Air Vice-Marshal Andrew Pulford (2008–2010)
• Major General David Capewell (2010–2011)
• Air Vice-Marshal Bob Judson (2011–2013)
• Major General Patrick Sanders (2013–2015)
• Air Vice-Marshal Edward Stringer (2015–2017)
• Air Vice-Marshal Andrew Turner (2017–2019)
• Major General Charles Stickland (2019–2021)^[4]
• Air Vice-Marshal Allan Marshall (2021–2024)^[5]

Assistant Chief of the Defence Staff (Personnel Capability)

Since 1992, the Defence Services Secretary has usually holds the appointment of ACDS(P) as a secondary role.

• Major General Brian Pennicott (1992–1994)
• Air Vice-Marshal Peter John Harding (1994–1998)
• Rear Admiral Rodney Lees (1998–2001)
• Major General Christopher Elliot (2001–2004)
• Air Vice-Marshal David Pocock (2004–2005)
• Rear Admiral Peter Wilkinson (2005–2007)
• Major General Matthew Sykes (2009–2010)
• Air Vice-Marshal David Murray (2010–2012)
• Rear Admiral Simon Williams (2012–2015)
• Major General Richard Nugee (2015–2016)
• Air Vice-Marshal Garry Tunnicliffe (2016–2019)
• Rear-Admiral James Macleod (2019–2022)
• Rear-Admiral Philip Hally (2022- present)

Assistant Chief of the Defence Staff (Policy)

• Air Vice-Marshal John Gingell (1975–1978)
• Rear Admiral Jock Slater (1985–1987)
• Air Vice-Marshal David Hobart (2001–2004)^[6]
• Major General Andrew Stewart (2004–2006)
• Rear Admiral Alan Richards (2006–2009)
• Major General Jonathan Shaw (2009–2012)

Assistant Chief of the Defence Staff (Reserves and Cadets)

The ACDS(R&C) is the senior reservist of the British Armed Forces. They are responsible for tri-service policy relating to the reserves and cadet forces. The appointment was created in 2004.

• Major General Gerald Grosvenor, 6th Duke of Westminster (2004–2007)^[7]
• Major General Simon Lalor (2007–2010)^[8]
• Major General Greg Smith (2010–2013)^[9]
• Major General John Crackett (2013–2016)^[10]
• Major General Ranald Munro (2016–2019)
• Major General Simon Brooks-Ward (2019-2022)^[11]
• Major General Marc Overton (2022–present)^[12]