The Twentieth Midwest Probability Colloquium will be held at Northwestern University on October 23-24, 1998. This meeting attracts 75-100 researchers in mathematical probability theory, mostly from the universities in the greater midwest area but also from more distant locations. This year the program will feature two lectures by Professor Ioannis Karatzas of Columbia University on the topic of financial models. In addition there will be two other speakers of one hour each. The format encourages informal interaction among the participants by means of a reception on Friday evening and long break periods between the talks. NSF funds will be used primarily for travel support with emphasis placed on encouraging attendance by graduate students and junior researchers.