This manuscript reviews what is currently known about natural and artificially introduced gene drive systems, and discusses what factors contribute to the evolution of resistance (or not). It concludes with a discussion of what strategies might best be employed to delay the evolution of resistance in artificial gene drive systems. I found the manuscript to be interesting and well-written, and was unable to identify any particular gaps in the material that was covered. I only have some minor suggestions for improvement.

Lines 96-100: It's not exactly clear how these two categories correspond to the information in figure 1. Does a = 1a and b = 1b? Or is b = 1b + 2? Could be useful to clarify.

Section 2.1: Very many different types of gene drives are covered here. I think it would be helpful for the reader to include some sort of table which briefly summarizes the mechanisms and differences between them.

Lines 304-308: Presumably a male-determining locus such as SRY is meant here. It would hurt to state it explicitly if so.

Lines 350-356: This is a very interesting idea!

Lines 377-394: I think this sort of effect will be inherently difficult to study, since it seems to build on existing mechanisms for sexual selection of high quality mates. That means that it might be difficult to detect differences between populations with and without the drive gene. I think it could be good to mention this caveat.

Line 528: Is this the name of the locus or an acronym? If it's an acronym then it could be excluded since it doesn't re-occur in the text.

Lines 589-591: In addition, selection to evolve another mechanism will probably be substantially weakened once an effective mechanism of one type has started to establish within the population.

Lines 656-661: I found this section a bit vague. It's not really described how resistance can be neutral/beneficial. I think the findings of the papers cited here need to be described in a bit more detail for readers who aren't familiar with them.