Joan Daemen was born in 1965 in the Belgian region of Limburg and grew up there in the village of Achel. After getting his degree in Electro-Mechanical Civil Engineering at the Katholieke Universiteit Leuven in 1988, he started a PhD in Cryptography as a member of the research group COSIC (COmputer Security and Industrial Cryptography). From that time, Joan has been actively cryptanalyzing and designing block ciphers, stream ciphers and cryptographic hash functions. He completed his PhD thesis in March 1995.

After obtaining his PhD, he quit the field of cryptography and computer security for about a year to work for Janssen Pharmaceutics, a Johnson and Johnson company, in Beerse, Belgium. Then, he returned to the field with positions first at Belgian bank Bacob and shortly after that to Banksys, the main Belgian operator for ATMs and EFT-POS terminals.

In late spring 1998, the commercial success of the Proton Electronic Purse, a Banksys development, led to a spin-off called Proton World International. The mission of this newly found Brussels-based company is to be a technology provider, delivering end-to-end solutions in the field of smart card applications. Proton World focuses on applications that require a high level of security such as payment systems and banking. As part of the Banksys security engineering team, Joan switched to Proton World when it was founded and still works there.

Today, Joan is primarily active in the design of cryptographic protocols for smart cards, the architecture of multi-application smart card management and personalization systems.

After leaving university, Joan has continued to design and publish cryptographic primitives on a regular basis. On many occasions, he has collaborated with his former COSIC colleague Vincent Rijmen. In 1997, this led to the publication of their innovative and influential block cipher design Square, the predecessor of Rijndael.

In his most recent cryptographic publications, Joan has concentrated on the analysis and design of mechanisms and cipher features to protect against attacks that exploit implementation weaknesses.