The present invention relates to fusion molecules composed of human interleukin-3 (hIL-3) variant or mutant proteins (muteins) functionally joined to a second colony stimulating factor (CSF), cytokine, lymphokine, interleukin or IL-3 variant. These hIL-3 variants contain amino acid substitutions and may also have amino acid deletions at both the N- and C-termini. The invention also relates to pharmaceutical compositions containing the fusion molecules and methods for using them.