Combinatorics deals with discrete structures that are used, for example, in the modeling of road networks. In extremal and probabilistic combinatorics mathematicians use probability theory to try to find and describe optimal discrete structures. Haxell provided fundamental theoretical contributions to an important branch of combinatorics, graph theory. A graph is a kind of net by which, for example, the structure of a road network can be examined. At Freie Universität Penelope Evelyn Haxell along with Tibor Szabó will explore special problems in graph theory and possible applications of game theoretical methods in combinatorics.

Haxell earned her doctorate in mathematics in 1993 at the University of Cambridge. Then she continued her research at the Department of Combinatorics and Optimization at the University of Waterloo in Canada where, in 2004, she accepted an appointment as professor. Haxell is an associate editor at leading magazines dealing with combinatorics and algorithms. In 2006 she was awarded the Krieger-Nelson Prize by the Canadian Mathematical Society.

In recognition of outstanding achievements in mathematics, the Humboldt Foundation grants up to 25 Friedrich Wilhelm Bessel Research Awards annually. As part of the award, the recipients are invited to spend a period of up to one year cooperating on a long-term research project with specialist colleagues at a research institution in Germany. Nominations for the award are made by researchers in Germany.