Working on a book (160 p), how can I lock/safe gard the finished pages?

[Pieter J62]

Hi, I'm working on a book with appr. 160 pages. Now at 99 and I like to 'freeze' or 'lock' everything precious that has been found correct. 
Is there a way or a work around? Should I split the document up in e.g. 4 large sections and join them when finished?

[Derek Cross]

Do you mean preventing alterations to the PDF produced from your InDesign? You can do that, though experts can soon break it. Or do you mean producing several InDesign documents and joining them into one? If so, you use the Book feature for this (File > New > Book).

By the way, don't forget to save incrementally named copies of your book files, externally as well as internally, to prevent loss in case of corruption or something else.

[Pieter J62]

No, not pdf's. The actual InDesign file. But thinking 'Book' is prob. a good idea. 

[Derek Cross]

You might find this documentation on creating book files useful: https://helpx.adobe.com/in/indesign/using/creating-book-files.html

[Peter Spier]

Make backup copies of things as they are approved.