[2] In an interview with The Hoopoe, McPherson explained his reasons for writing the book and the extensive field work that it involved:[3] I prepared Pitcher Plants of the Old World in response to the lack of available information on dozens of species of Nepenthes.

After graduating from university in 2006 at the age of 23, I began three years of intense research focusing on Nepenthes and Cephalotus, and spent a cumulative total of eighteen months in the field.

Over the last three years, I climbed over one hundred mountains across Southeast Asia in search of species of Nepenthes.

[7] Nepenthes hamiguitanensis—which would be described in McPherson's next book, Carnivorous Plants and their Habitats—is treated here as a natural hybrid between N. micramphora and N. peltata.

[9][10][11][12] In their review for the journal Phytotaxa, Maarten J. M. Christenhusz and Michael F. Fay wrote:[10] This is to date the only publication dealing with the genus Nepenthes throughout its geographical range.