Like many libraries, Seton Hall University Libraries has suffered budget cuts that forced a reduction in serial subscriptions. As science librarian, I report on my efforts to streamline subscriptions and to address the question "Why are science journals so expensive?" Our science journals are significantly more expensive than journals in other areas. Our commercially published science journals are 25% more expensive than those from non-profit publishers, although the difference is not statistically significant. I discuss the reasons for the high cost of science journals, which involve a complex interaction between supply and demand and academic culture. (Contains 3 tables and 2 figures.)