system
Given the following post, respond as if you're commenting on Reddit:
human
Writing first book - when to approach publishers?

I'm a mid-career (10 years post PhD) UK academic in psychology, and I'm writing my first popular science book. I've written about 2.5 chapters of 10 or 12. Should I approach potential publishers before I've finished a draft with a proposal? Then they could advise on length, format etc. Or should I wait until I've drafted the whole thing before approaching publishers? Advice from those that have done it before especially welcome.
gpt
**STOP!** 

Contact some publishers and see if they are interested in your proposal  -tell them you have two sample chapters (many require a sample chapter or two) and can provide an outline of the rest.

Do not write a whole book without a contract!!!!!!!