- page 12, third bullet point: the radii r_1 and r_2 need to be equal.

- page 76, Exercise 5.3.1: the images of two different lifts need not be disjoint. The correct statement is that the set of values where the functions agree is either everything or the empty set.
- page 76, Lemma 5.3.5 and Figure 5.9: the roles of X and Y are reversed between the text and the figure, which then leads also to an inconsistency in the last sentence of the Lemma, "Repeat this process using..."
- page 93, Example 7.1.3: the second, third and fourth lifts should have (t+1)i instead of (ti+1), (t+2)i instead of (ti+2), etc.
- page 117, Table 8.1: the bottom right entry of the character table of S_3 is -1.