The Fifth International Conference on Micro Total Analysis Systems, also known as JlTAS 2001, will highlight the latest exciting events in the world ofminiaturized devices and systems for performing chemical and biochemical experimentation This conference has become mandatory for those of us working in this field as it is indeed helping to define our discipline. We are grateful to the people of the MESA Research Institute of the University of Twente, particularly Piet Bergveld and Albert van den Berg, for starting this meeting in 1994. Their original intention was for the JlTAS meeting to be a small informal workshop. This workshop flavor was sustained through the second meeting held in Basel in 1996, but already in 1998 at the third meeting in Banff it was clear that the "workshop" had become a conference with 420 attendees. It was due to this clearly growing interest in microchemical systems that it was decided we should consider gradually moving toward an annual format and prepare for the possibility that the meeting would increase in popularity. Albert van den Berg was still yearning for a workshop at the JlTAS 2000 meeting and planned a single session format. Again there was a large increase in submitted abstracts (more than 230 total) and a further increase in attendance. The JlTAS steering committee again agreed that we would have to prepare to address the demand the meeting was receiving.