The closest most people come to partworks is watching the adverts on TV offering the chance to collect an A to Z guide to your PC, or build a unique collection of die-cast model motorcycles. These titles rarely cause a ripple in the wider media pond, but the sector is estimated to be worth £120m a year and has just entered its peak sales period.
Now is the time when consumers, freshly laden down with resolutions to start a new hobby, are most susceptible. They are lured in with cut-price launch issues and blitzed with TV advertising to bring them into the fold.
In most cases, once they are in, they will be with the publisher for the long run, sometimes spending more than £200 to build their collection.
The temptation to take advertising to recover some of these heavy media costs must be great, but one that is resisted. Susie Cullen, marketing director of partwork publisher Eaglemoss, says: "To include advertising would diminish its value as a collectable reference source and we know from research that our consumers appreciate the fact we don't."
The nature of partworks is such that economies of scale play a critical role in determining a product's success or failure. This, coupled with the fact that the business model works more effectively when higher margins can be made on later shipments, are two of the key financial considerations for companies working in this sector.
Cullen sums up the difference between magazines and partworks: "Partworks have a start and a finish. A heavy media TV launch gets everyone to buy at a single point in time - it's a one-off hit and our challenge is to keep loyalty and attention."
In 2002 the retail sales value of partworks in the UK was £105m, projected in 2003 to exceed £120m. As a magazine sector it ranks fourth (in retail revenue) behind TV listings, women's weeklies and women's monthlies.
Up-front launch costs are high - Cullen says a typical partworks media spend on a single launch would be between £1.3m and £1.4m on a national TV campaign.
In a year, that equates to an investment of between £5m and £8m, putting pressure on customer retention to ensure pay back.
Indeed, the total amount spent by UK partworks publishers on TV is between £12m and £15m a year, based on an average of around 12 launches a year.
Broadly, Eaglemoss expects a partwork launch to sell anywhere between 300,000 and 800,000 copies.
Cullen admits that the Eaglemoss route to market via the news distribution system makes the company somewhat detached from its end consumer. But partworks publishers need the news distribution channel to sell the very first copy, so their advertising launch burst is designed to drive consumers to the newsagent.After that initial sale, however, the relationship is less well defined, as partworks publishers have the ability to convert part of their readership to subscriptions - so it is very much a marriage of convenience.
There is clearly an appeal among UK consumers to collect and build over time, particularly prevalent in the children's market where, if the product is well targeted, children will become very loyal and in most cases involve their parents. This creates something of a 'club' mentality that often manifests itself on the product's website chat rooms and message boards.
If a partwork is delivering course-based information then people do not want to be overwhelmed - receiving a step-by-step, course becomes far more digestible for the learning process.
Also, not everyone wants to go out and spend a significant sum of money on a large book. Paying as you go allows flexibility - if consumers become bored with the project, they can stop collecting.
Eaglemoss has dealt with competitive threats to its business by developing collections of items that work well alongside a magazine and appeal to the collecting instincts of consumers.
Cullen explains: "Eaglemoss decided to offer a figurine collection with editorial material behind it, allowing us to use our distribution network to put something complimentary to magazines through the traditional target market that has worked for us."
Successes include a bird collection and Lord of the Rings for adults; and Real Robots, which is delivered in component parts each week, for children to build a robot. "We're no longer just reference or course- based material - we are adding value to our products, at higher cover prices," adds Cullen.
The typical adult consumer is predominantly female - C1, C2 - so supermarket magazines, such as Safeway Choice, are examples of media used to promote cookery products. However, a swing to more male consumers in the last three to four years has been driven by the growing number of computer publications. Cookery remains important, but some companies regard the sector as too crowded, not just in partwork terms but overall, including cookery magazines and books. Children's products are regarded by the industry as very much the "coming sector" with a growing trend towards character-based learning concepts.
Companies attach a lot of importance to product development, not only to capture the moment (in terms of consumer trends), but also to reduce the risk of failure.
Product testing is critical in this market.
However, companies have a different perspective when it comes to editorial content - some prefer to outsource to specialist agencies, whereas others have a substantial in-house team. The industry is campaign focused, and January is a particularly active month, because of lower media costs and the need to be apart from melée of the Christmas gift market. The internet has been embraced warmly by Eaglemoss, which has invested £150,000 into its website. Character licensing products such as Jackie Chan benefit from the interactive nature of the website. "It's a very strong customer loyalty tool," confirms Cullen.
With the collectables market showing no signs of having reached maturity, and reinventing itself continually with educational products and licensed concepts, the outlook for those publishers who can accurately predict consumer trends and devise ways to reduce attrition rates, remains positive.
