The survey as transcribed by William Mooney in 1835 covers the entire of County Cavan and is listed in order of barony. It appears to be a unique document, and no similar survey has been discovered for any other county. The format, purpose and content of this work differentiates it from other surveys from around the same era including the Civil Survey of Ireland 1654-56 and the 1659 Census of Ireland in which both sources, Cavan returns are not found.
In his essay in Common Ground on the evolution of estate properties in South Ulster 1600-1900 P.J. Duffy states that both Cavan and Monaghan counties were reserved for disposal to the Cromwellian army. This essay is very helpful in providing the background and context to the making of the Commonwealth Survey.
The order in which the parishes and townlands are listed in the transcribed document can be difficult to navigate. For instance, the parish of Denn occurs over pages 7, 8, 24 and 50. There are a number of reasons for this. Firstly the parish of Denn straddles three baronies, Loughtee Upper, Castlerahan and Clanmahon. Also, the polls are listed by proprietor and not alphabetically which means the order in which they occur can be confusing. This is further not helped by the subdivision of the portion of each parish in each barony into arable and waste lands.
 P.J. Duffy, ‘The Evolution of Estate Properties in South Ulster 1600-1900’ in Common Ground, 1988, p. 99.
On fieldwork assignment for the topographical department of the Ordnance Survey, which began in March 1834, the great scholar John O’Donovan wrote his famous Ordnance letters. These letters relayed his thoughts and requests to headquarters in the Phoenix Park and were dispatched several times a week from wherever he happened to be around the country. In a letter dated 27 May 1836, writing from Cavan to Lieutenant Larcom, he mentions the Commonwealth Survey thus:
I find an authority very frequently quoted in the Cavan Name Books under the title of ‘Commonwealth Survey’ which is amazingly correct in every instance, in fact, the most correct document I ever heard of as far as regards the orthography of names of Townlands (see Cornashesk in the Parish of Lurgan). Can this Survey be had for the county of Leitrim, or does it extend beyond Cavan?
 Patricia Boyne, John O’Donovan (1806-1861): a biography (Kilkenny, 1987), p. 13.