In this prospective study distress, neuroticism and time since diagnosis were investigated as determinants of spousal support behavior (i.e. protective buffering and active engagement) in a group of 92 partners of women with breast cancer. Distress and neuroticism were assessed at three months after diagnosis while protective buffering and active engagement were assessed at three, nine and 15 months after diagnosis. Results indicate small but significant decreases in protective buffering and active engagement over time. Moreover, initial distress and neuroticism were found to be strongly and positively related to protective buffering at all three measurements. In addition, less distress was associated with more active engagement in especially individuals scoring relatively low on neuroticism, but only at 3 months after diagnosis. Copyright © 2007 John Wiley & Sons, Ltd.