The publisher says no: bad luck! But don't be disheartened: have they explained their reasons? Perhaps they don't take that kind of study any more – perhaps they know someone who does: ask! Did they feel it wasn't publishable in its current state: what where their precise criticisms? Do you agree with their assessment? Is there anything you can do to address their points? Set yourself a list of tasks and give yourself a deadline: work on the chapter, bring it up to scratch and send it off again, either to the same publisher if they encouraged you to do so, or to another one if their no was definitive. NEVER GIVE UP! We all know the sob stories of the literary greats who couldn't find a publisher and once they did were slammed by the press. This is a heroic task of rejection and exaltation, and it may take a while (think of it in epic terms!).
The publisher says yes: well done and phewee! But the job is not finished. You now need to agree with the publisher a date to deliver the whole manuscript. (At this stage, you may receive a contract, although some small academic publishing operations do not issue these.) It is vital that you agree a feasible delivery date, and that you stick to it once it is agreed. Late delivery jeopardises the chances of publication. At this stage, take every possible care to revise your MS. in accordance with the publisher's house style and other instructions to authors. This can save a lot of trouble later on.
Once submitted, the manuscript will then go to one or two expert readers; their reports will be weighed by the commissioning editor or by an editorial committee; publication will be recommended (or not – anything can happen!) either in its current state of preparation (rare!) or with revisions. Revisions can be fairly minor or entail large chunks of rewriting or even fundamental rethinking: take the criticism on the chin, gear yourself up, and start work (see The writing process). Once the revised manuscript is delivered the publisher may or may not send it again to a reader or readers, to see whether the revisions have been satisfactorily carried out. When they are satisfied with the manuscript, they may issue a contract, if they have not done so already, and the book will go into production. The manuscript may first go to a copy-editor, who will examine it carefully for any typographical or other presentational errors, and make sure it is in accordance with house style. You will then have to check the copy-edited manuscript, before it goes for typesetting. The earlier mistakes are detected, the easier it is to remedy them. Do not wait until proof stage to make corrections: if the error is yours, rather than the typesetter's, you may be required to pay correction costs. When the proofs are produced, you need to examine them very carefully for any errors that have crept in or that have survived earlier examinations. You will probably also be asked to compile an index. So there is still a lot of work to do once the manuscript is submitted, but it feels much less onerous when you know you are on the road to publication. Very occasionally, a publisher may have a late change of heart, owing to a take-over or some other reason, and no longer be able to publish your book. If this does happen, ask if you can take your readers' reports to another publisher to smoothen the way - they will probably be happy to let you do this in the circumstances.
How long will it take?
The whole process, from first approach to publication, can easily take a couple of years. Each stage of the decision-making process, except for a swift no at the very first hurdle, is likely to take about a month (not less), particularly when a long manuscript has to be dispatched to a probably already very busy expert reader – the time scale here is more likely to be three months. A polite email will elicit the state of progress. Yet however long the publisher seems to be taking, once you have agreed on a date for manuscript delivery with your publisher, KEEP TO IT!