Aims: To understand the extent to which bush fire fighters can reliably and accurately monitor their cognitive performance following sleep restriction over a 3-day simulated fire-ground campaign. Methods: Twenty-five participants performed a total of 14 circuits over three days that involved intense physical work. Participants received an 8-h sleep opportunity for the first night, and were restricted to 4-h sleep opportunities on nights two and three. Reciprocal reaction time on the Psychomotor Vigilance Task (PVT) was assessed at the end of each circuit, with self-reported measures of performance being attained before and after each cognitive battery. Results: A main effect of day was discovered for reciprocal reaction time F(2.75, 65.92) = 10.86, p<.001, p2= .31; pre-performance ratings, F(3.03, 64.06)= 6.53, p=.001, p2= .21; and post-performance ratings F(2.74, 57.58)= 9.31, p<.001, p2= .31. Standard contrasts revealed that despite no significant difference between reciprocal reaction time on day 2 and day 3 (p=.077), significant differences were found for both pre (p<.05) and post (p<.05) subjective ratings of performance. Pre and post ratings of performance were found to have no significant relationship with objective performance. Discussion: Results indicate that fire fighters can accurately identify performance decrements after experiencing partial sleep restriction, despite being unable to identify the degree to which their performance would be impaired. The use of subjective judgments of fatigue and performance appear to offer an effective, efficient and cost effective tool in fatigue management strategies. Some caution must be taken however, as it is possible that fire fighters may over or underestimate the degree to which their performance will be affected.