Access

Hi Stuart Thank you for the post, welcome to the forum, in answer to your question, (it would be great) but you cannot make some fields read only and others not, but what you can do is create a sub form, and have the read only fields in the sub form.
If you consider your table; choosing the fields to be editable and those not editable, then split your table into two tables and join them on a one to one relationship, (both sides will have the same primary key,) you can then join them, applying referential integrity.
Then: Make 2 forms, one from each table, and in the form to be kept read only, in design view apply the simple security restrictions; No Edits, No Additions and No deletions. You should then format this form to hide all borders, backgrounds and other items such as scrollbars, selection buttons, lines and navigation buttons.
Open the 'editable form' in design view, then from the toolbox select the subform tool and click/draw in the 'editable form,' when you are asked to link a form; choose the 'non editable form' and you will nest the sub form inside the main form. It sounds a little long winded, but it works, I've just tried it. It was a great course today, thanks, best regards Pete