What are the differences between project accounting and accounting for a firm as a whole?

Project accounting basically is the accounting where we based our accounting system on project base.
In my experience in a big construction company where a chartered accountant maintain firm accounting and did not emphasis over project accounting.
the result was this that company has accounts but did'nt have project accounts and failed to get a detail on what project company earned or beard loss.
In the absence of project accounting company also failed in cost management.