The Australian Post Office (PO) has issued souvenir (event)   covers (not to be confused with first day covers) since 1970 to commemorate events of (a) major public interest—royal visits, world conferences, sporting events etc and (b) postal services events (opening of a new PO and centenary celebrations of others). Such covers are usually promoted in conjunction with commemorative postmarks. By the end of December 1996, 224 souvenir covers had been produced; the Catalogue lists these.

In addition, the PO has issued blank (unserviced) general purpose philatelic covers for use when souvenir covers are not available. In March 1991, the Fifth (and current) series, Australia Through Stamps, was released, bringing to fifteen the number issued since 1972; the Catalogue fully details the fifteen envelopes.

Recently a third category, more correctly a sub-category, of cover reached catalogue status when the latest update was released in August 1997. In Supplement No. 1 (published October 1987) eleven Golden Wattle and Map general purpose covers were priced and illustrated at the back of the book. Back of Book listing arose out of doubt about the status of the covers which had a few lines of text applied to them by means of a rubber stamp (RS). To add to the confusion some covers were prepared at the local post office while others were done at head office. An assortment of coloured stamp pads was used to affix the cachet. The covers were issued in the period 1972-76 for the opening of some post offices, mainly in NSW and Victoria. In the last ten years fourteen more covers have surfaced. The author has illustrated and priced the RS covers having satisfied himself of their official status as that are the Australian Post Office. The catalogue values of the seventeen RS issues (comprising 25 covers) total a staggering $6,450.

The Catalogue, the reference work in its field, is devoted to the study and classification of the above two types of covers, appropriately called Special Events Covers (SECs) and General Purpose Covers (GPCs) by the author.

The status coding of each cover, as used in the first edition (1982), has been continued, as many covers were issued without publicity or notice in the Australian Stamp Bulletin, like the $500 Gold Coast envelope illustrated on the front cover of the Catalogue. Few collectors were aware of the existence or status of many of the envelopes, including the Gold Coast cover, until Mr Almeida studied and listed them. Forty-six covers are valued at or more than $100 each.

Catalogue numbers (GP, SE and RS) have been allocated by the author and the latest market values incorporated. Every cover is illustrated, together with line drawings of the ten envelopes knives or cutting dies used for the different prints of the general purpose cover series.

The Catalogue is a priced, numbered, chronological, fully illustrated listing with 268 covers. It has 186 pages in the international B5 size, with card covers.  The full catalogue comprising the original book and all four supplements is priced at $75.