Have you ever wondered how trends are born and what determines their longevity? It is impossible to formulate an all-encompassing theory, but having worked in the fashion industry I have been exposed to this phenomenon more than most. It is a complex process, but here are some of the elements.

One big factor in the birth of a trend is fabrication. This is where the supply chain starts, because without fabric you can’t make a product. Fabric producers need to predict the trends, or better yet, determine them in order to know what to produce for future seasons. So the big fabric mills host trade shows like Premiere Vision, which takes place in Paris every September. Designers attend these shows to get inspiration for their upcoming ranges.

Designers also visit top trend houses like Promstyl to get the creative juices flowing. They document their inspiration and are also very much inspired by what they see on the street. Every city has fashion pioneers who are creating bold new outfits that challenge the current norms, and even making their own creative clothes. Street style is a major source of inspiration, so it’s possible that you could be setting the next big trend without even knowing it.

And then there is popular culture. Trends in other aspects of our lives are influencing designers all the time — up and coming bands, new movies and television shows, literature, technology.

Having combined all this inspiration with their own creative energy, top designers show their resulting collections at Fashion Weeks all over the world. They typically do this twice a year – in Spring and in Autumn. The shows are scrutinized by the retail industry and press. It’s then up to fashion buyers, editors of fashion  magazines, retail management and mainstream designers who directly work with manufacturers to pick and choose the styles and trend direction for retail stores. Some trends barely change and what you see on the catwalk is what you’ll see in stores. Some trends are adapted or watered down to look more “normal” for everyday style. And some trends never filter through to retail stores. There are also trends that take a couple of seasons to filter through so not all hope is lost after rejection the first time round.

Once trends hit stores, consumers have a say in the matter too. If they like what they see, the trends sell well. If they don’t, trends get marked down as soon as possible. Top selling trends are repeated the next season and often become mainstream basic lines. So you as a consumer have the power to keep a trend alive and see it become a mainstream success.

But there is still so much that is unexplained. I always wonder how it happens that there is often such consistency across designers in the new trends we see emerging on the runway. Who decided that skinnies should come back into fashion, or that hemlines should be raised, or that turquoise should be the next big colour? Is there a top secret meeting somewhere to ensure that strong shouldered looks make a comeback? How do top trend houses decide that grunge is back or that safari themes are all the rage?

Or perhaps there is a big element of chance in the birth of a trend. Rather than something being consistent across designers because it is a new trend, perhaps something is a new trend because it happened to be consistent new theme on the Fashion Week runway.

If you work in the industry, I’d love to hear any insights you can offer on this elusive process. As a consumer, do you have any theories of your own on the birth of trends?