Professor Johnson will continue his research into a selection of subfields of matrix analysis. These include combinatorial issues in matrix analysis, the permanent-on-top conjecture and related inequalities, Hadamard products of matrices, nonnegative and M-matrices and other topics in matrix analysis. This research covers a very broad range of topics from the theory of matrices (linear algebra). Dr. Johnson has had remarkable success in all of these areas before, and will undoubtedly continue his prolific contributions to the subject. He is very influential with both students and peers. He generates many joint papers with co-authors from around the world. He also has joint work with his students. The work in this proposal also has many applications in the broad range of mathematics which today uses linear algebra.