This study of n = 201 knowledge workers examines positive and negative spillover between work and home and its interrelation with life satisfaction. Additionally, it accounts for the direct effect of role importance on life satisfaction and its moderating effect on the interrelation between spillover and life satisfaction. Central to role importance is the degree of attachment that an individual places on family role and career role. Positive spillover from home is interrelated with higher life satisfaction, whereas negative spillover from work is related to lower life satisfaction. Family role importance and career role importance are associated with higher life satisfaction. For respondents with higher family role importance, there is a stronger interrelation between negative spillover from home and lower life satisfaction.