In order to improve our understanding of mediating variables. This paper examines the relationship between high-performance work practices (HPWP) practices and employee attitudes. Using a randomly selected, national population sample, clear evidence was found for a positive relationship between HPWS practices and the attitudinal variables of job satisfaction and organizational commitment, implying that HPWP can provide win win outcomes for employees and employers. However, the study also tests ndash from an employee perspective ndash the lsquocomplementarities thesisrsquo and finds Positive interaction effects among HPWS practices. This strengthens the argument that there are likely to be limits to the positive outcomes of HPWSs for employees. Evidence of sequencing in the employee attitudinal responses to HPWSs was also found, with job satisfaction as the key mediating variable. Regression analysis showed that there is a positive significant relationship between High performance work practices and job satisfaction, and also there is a positive significant relationship between High performance work practices and organizational commitment.