Every official release, may it be 7", 12", CD or cassette, will be given its own catalogue number. Both numbers and letters are used for catalogue numbers to identify the particular release and the format. The following numbers are used at the end or sometimes at the beginning of the catalogue number to identify the format:

• 0 = 12" vinyl records
• 1 = Albums on vinyl
• 2 = CD-singles or CD-albums
• 3 = Videos
• 4 = Cassette-singles and cassette-albums
• 7 = 7" vinyl records

Most European releases and also Canadian 7" and 12" releases have a six figure number starting 92 plus the appropriate digit at the end to identify the format. In addition, the German releases have a circled N after the catalogue number to signify that it is a German release. The Spanish 7"-singles have an S placed in front of the catalogue number or a circled S behind it and the 12"-releases have MS (standing for Maxi-Single) placed in front of the catalogue number. The Australian 7", 12" and album releases usually take the European number without the 9 on the front and have the format number in front. The USA releases usually have the catalogue number in the same format as the Australian releases printed on the record labels and have the format number printed at the end (sometimes with a 9 placed in front of the catalogue number) on the sleeve. The USA promo 12"-releases have "PRO-A-" in front of a 4 digit number. UK single-releases have a unique number printed on the release in front of the European number. For 7"-releases, this catalogue usually starts with a "W" followed by four digits. Extra letters are added on the end of this number for 12" releases, limited editions, promos and picture disc as follows:

• B = box-set (e.g. "Early Morning" W0012B)
• CD = CD-singles
• DJ = Disc Jockey Copy (e.g. "I Call Your Name" W9462DJ)
• EP = Extended Play, usually 7" vinyl records (e.g. "I Call Your Name" W9462EP)
• P = Picture Disc, may be used in conjunction with T for 12" picture discs (e.g. "Cry Wolf" W8500TP)
• SAM = Promotional copy (e.g. "You Are The One 12", SAM 498)
• T = Regular 12" vinyl-release
• V = 7" vinyl gate-fold and inserts (e.g. "Cry Wolf" W8500V and "You Are The One" W7636V)
• W = 7"-release or 12"-release (where TW is used) with free poster, postcards or special sleeve (e.g. "Manhattan Skyline" W8405W and "Touchy!" W7749W)
• X = Limited CD-single with postcards (e.g. "Shapes That Go Together" W0236CDX)

The UK LPs also have unique numbers that start with "WX" followed by two digits with the cassettes having the same number with a "C" at the end. The UK CD-albums have the same catalogue number as the European CD albums. We will usually just list the UK catalogue number unless it is a limited edition, in which case we will list the `European number' in brackets afterwards. French releases have an extra code which is usually placed after the European number and indicates the format of the release (these codes are also printed on the German releases where it is often noted that they are for the French market):

• WE 171 = 7" vinyl (note that the second figure is the one actually revealing the format)
• WE 221 = 12" vinyl
• WE 381 = Vinyl-albums
• WE 491 = Cassette albums
• WE 739 = All CD-singles post '88
• WE 731 = CD-singles ("The Blood That Moves The Body", "Touchy!" and "You Are The One")
• WE 831 = CD-single ("Stay On These Roads")

The German made CD-albums are given an additional code for the French market which is of the form WE 8 followed by two other digits but these vary from release to release so we will list them under the appropriate releases.

Some countries have completely unique catalogue numbers. The Japanese 7"-releases start with "P-" followed by 4 digits. The Portuguese 7"-releases also have unique catalogue number with 7 digits, starting 159 and ending with a 7. Brazilian 7"-releases are also given unique catalogue numbers which are seven digits long (?). The Brazilian 12" promo releases are often given numbers of the form WEA # with a 2 digit number on the end while others take on a more regular form.