In 1988, he left Olivetti to start the Active Book Company, investing one million pounds of his own money. Not wanting to repeat the mistakes made by Acorn, which had kept its technology to itself, he demonstrated the Active Book to as many large companies as he could. AT&T acquired Active Book and incorporated it into EO in July 1991. Hauser became Chief Technical Officer and Chairman of EO Europe. EO folder on Friday 29 July 1994.

In 1990, Hauser was involved in spinning out Advanced RISC Machines (ARM) from Acorn.

In 1993, Hauser set up Advanced Telecommunication Modules Ltd with Andy Hooper. The company was acquired by Conexant Systems on 1 March 2004. He founded NetChannel Ltd in June 1996 as a holding company in order to begin work on marketing the NetStation. Net Channel was sold to AOL in 1998. He claimed in the 1990s that the networking technology used for AppleTalk was based on the (unpatented) Cambridge Ring.

In 1997 he co-founded Amadeus Capital Partners Ltd, a venture capital company, and in 1998 he co-founded Cambridge Network Ltd with David Cleevely and Alec Broers.

In 1998, Hauser was elected into an Honorary Fellowship of Hughes Hall, Cambridge, and he was also elected into an Honorary Fellowship of Kings College with effect from 1 January 2000. In the same year he was awarded the Mountbatten Medal.

In 2000, Plastic Logic was founded, with Hauser as chairman.

Hauser was awarded an Honorary CBE for “innovative service to the UK enterprise sector” in 2001.

On 14 June 2001, the Hauser-Raspe Foundation was registered as a charity by Dr Hermann Hauser and Dr Pamela Raspe to advance education.

On 8 July 2002, Hauser was elected as a Fellow of the Institute of Physics and as a Fellow of the Royal Academy of Engineering.

In August 2004, Amadeus Capital Partners led the Series B venture capital financing of Solexa Ltd and Hermann Hauser joined its Board of Directors. Solexa developed a next-generation DNA sequencing technology which became the market leader. Solexa was sold to Illumina, Inc (ILMN) of San Diego in January 2007 for over $600M. In 2009, Dr Hauser was announced as the first customer of the Illumina Personal Genome Sequencing service.

In 2005, Hauser received a Lifetime Achievement Award for his work as a venture capitalist and entrepreneur. The award was presented at the annual European Electronics Industry Awards in London.

As of 2009, Dr Hauser is the head of the East Anglia Stem Cell research network.

Dr Hauser is a Non-Executive Director of Cambridge Display Technology Ltd, a Non-Executive Director of XMOS Ltd and a Member of the Board of Red-M (Communications) Ltd. He holds honorary doctorates from the Universities of Bath and Loughborough and from Anglia Ruskin University. He is a member of the Advisory Board on the Higher Education Innovation Fund and of the UK’s Council for Science and Technology. Hauser was commissioned by the Department for Business, Innovation and Skills to write a report on technology and innovation in the UK, which contributed to the government’s fund for Technology and Innovation Centres.

In 2010, Eureka, in its “100 most important scientists”, placed Hauser at 51. He became patron for The Centre for Computing History in December 2001, 30 years after the launch of the BBC Micro.