This article shows 3 ways to convert a color InDesign document to grayscale (black & white) - Export PDF, Use color blend or Export image.

Do you want your users to be able to interact with your PDF document? This article will show you how to create interactive PDFs in InDesign.

PDF Files From InDesign: Convert Pages to Grayscale Steve Werner at Creative Pro discovered a clever way to export PDF files from InDesign in grayscale. This works in Indesign CS6 and later versions.