The company did not give any reasons for Paul Oosthuizen's resignation, but did thank him for his contribution.
Oosthuizen will only leave the company after it has released its year-end results to December.
He is a qualified chartered accountant and holds a B Com (Hons). After qualifying as a chartered accountant, Oosthuizen worked in the UK for five years, predominantly within financial services for companies such as NatWest Bank and Schroders Asset Managers.
He has extensive experience in the telecoms sector, working as a business consultant with KPMG Consulting, in London, and serving financial divisions for clients such as Vodafone, British Telecom, Carlton Television and AT&T Europe.
Oosthuizen moved back to Cape Town in 2003, joining Dialogue in 2004 as FD.
Dialogue is in the process of appointing a successor, and will make an announcement “in due course”, it says.
Related story:
Dialogue in talks

