Title: Multiplicative structures on spectral sequences I Authors: Daniel Dugger AMS Math. Subj. Class. 55T05 Department of Mathematics, University of Oregon, Eugene, OR 97403 email: ddugger@math.uoregon.edu Abstract: This is mostly an expository paper, recording basic facts about towers of homotopy fiber sequences. We show that a pairing of towers induces an associated pairing of spectral sequences, for towers of spaces and towers of spectra. In the hope that this might eventually be a useful reference for people, feel free to send me suggestions for things that should be improved (with the understanding that it might be a while before I get around to implementing them).