acknowledge receipt of a book proposal within a few days of receipt and ensure the efficient, fair and timely review of the book proposal
notify the editor and excuse him/herself from the review process if he or she feels unqualified to review the research reported in a manuscript or know that its prompt review will be impossible
treat the book proposal as confidential; the book proposal (or its existence) should not be shown or disclosed to, or discussed with, others
destroy/erase the book proposal and to inform the commissioning editor should they be unqualified to review the manuscript, or lack the time to review the manuscript, without undue delay
judge the manuscript objectively and in a timely fashion; referees should not make personal criticism in their reviews
inform the commissioning editor if there is a conflict of interest (see Declaration of 'conflict of interest'); specifically, referees should not review book proposals by a person with whom the referee has a close personal or professional relationship, if this relationship could be reasonably thought to bias the review
respect the intellectual independence of the editor/author(s)
explain and support their judgements so that editor/author(s) and commissioning editor may understand the basis of their comments
ensure that all unpublished data, information, interpretation and discussion in a submitted book proposal remain confidential and not use reported work in unpublished, submitted articles for their own research.
And must not:
Retain or copy the submitted book proposal in any form; to comply with data protection regulations, as appropriate.