As mentioned in Chapter 3, there are two factors that introduce subjectivity, and hence inaccuracies, in the determination of time standards . The first one is the determination of rating and the second is the application of allowances . While one can reduce the subjectivity from rating by rating each elemental performance at least twice and training the time study operatives, careless application of allowances makes it difficult to reduce the subjectivity it introduces into time standards . The determination of allowances for personal needs and unavoidable delay are straightforward, yet the application of allowances for fatigue is often problematic . In this chapter, we first discuss personal and delay allowances and then fatigue allowances .