Aaaah. The Hero’s Journey, only institutionalized, mass-produced, pretty low-stakes - and only becoming more of an adventurous hero thing, worth of telling tales of to grandchildren, provided the character in question dons a hat.

Pokémon training is a core component of the formative stages of humans in the Pokémon World, and getting familiar with Pokémon and understanding the value of cohabitating with them is something very important to teach for many societies. The world at large has solidified the concept into the form of an adventure or exploration, with certain elements of “coming of age”, in which youth engage by being sent out to the world with a Pokémon by their side. It is generally dubbed the Trainer's Journey.

Why? Well, in the glorious words of PEFE member Pykrete:

“Imagine you were offered the chance to get out of school for a year and travel with cuddly creatures on government dime when you were ten and too young to think of things like poor travel conditions.”

At age 10 or so, everything is an adventure.

In overall terms, a Trainer's Journey consists of an arrangement, at a societal level, under which children obtain a Starter Pokémon and are sent out in batches to explore the community around and beyond the confines of their district or province, out to meet many other Trainers and Pokémon - people and creatures with very different ideas, limitations, needs, goals or even physiologies. The exposure of this diversity at large contributes to the youth maturing faster, becoming more accepting and understanding of the world around them. Youth challenge one another in battles with their Pokémon, and thus seek out more, stronger Pokémon to build up and realize both their potentials.

By the end of the arrangement, Pokémon and humans return to their lives stronger and more prepared; moreover, the youth who have done particularly well during this Journey would likely be allowed to extend the duration of their journey to see if they eventually specialize in Pokémon training, becoming able to opt in to a number of jobs in the Pokémon world that require close connection and ability to work with Pokémon - such as Gym Leaders, Rangers or even, the idealized scenario, the Champion.

The concept of a Trainer’s Journey originates from ancient tradition which was itself lost to the time of the First Trainers, and was only mostly recovered and built into the foundations of the global enterprise seen today by the middle of the Previous Era.

It is told that the first Pokémon Trainers were young humans in the Third Era when the world was facing the Warring Triad of Kyogre, Groudon and Rayquaza. Preserved lore has it that while adults fought to defend the human settlements and the elderly were moved to protected zones, it was youth and children who took the first step of venturing beyond into the wilderness looking for opportunities, and the Pokémon from the Safehavens, understanding that these children were lacking in malice, would follow them and protect them during their trips until they could be returned safe and sound to the human settlements.

The most notable one of those assemblies happened when three youth who had taken under their wing and trained a couple of Pokémon, went to the Lake Trio to seek out a way to stop the Warring Triad, and seeing those Pokémon and humans had forged already an agreement to work together, the Lake Trio gave them their blessing. From the campaign that ensued, the foundations of "The Vow" between humans and Pokémon would be born, and while the facts are most likely incomplete if not wrong, and lost to time, the base sentiment behind it, that Pokémon would come to the aid of humans who desired to improve the situation of their world, remained and gave birth thousands of years later to the tradition of Pokémon training.

At the age of 10 (or about), families in aggregate take their children out of school for a prearranged period of time, and send them out to the world accompanied by a Pokémon partner. For a time of as much as a whole year, the children are intended to train their partner as well as others who are brought in by capture in a fair battle, and explore the region around their home while they challenge the Gyms that comprise the local Conference. This first instance of several youth leaving their homes and schools at once to traverse the world around them is usually dubbed Trainer's Leave.

This adventure is mostly paid by “the State”, providing some important services to the young Trainers for free or a marginal price; sometimes, older Trainers who are building their momentum to continue and enhance their own Journeys also provide various assorted services for running this adventure, such as tutoring and road guides. The adventure is organized and run on a municipality-wide scale, in which schools participate: most Trainers don’t go out there all alone, but in small classmate parties or at least they remain for the majority of the time close to their district or commune.

At the end of the adventure, the Trainer returns to the schooling system, though Trainers showing notorious skill or a history of success might be allowed to extend this journey until at most two full years.

The main measure of success during the time of the (first) Trainer’s Journey is that the Trainer, once signed to the regional League, would travel from city to city to challenge Gym Leaders. Earning enough badges from those leaders within their regional League (eg.: eight in Kanto) qualifies the Trainer to enter that year’s Conference Tournament, where trainers engage each other to discover who’s the very best like no one ever was at the sport.

A Trainer who has collected enough badges, and ideally gone through the Conference Tournament no matter their ending position, and has shown a good performance and mindset in training and other related activities, can be allowed to extend the duration of their Journey for up to another whole year. After this year, Trainers usually have to return to schooling for a time no matter what, before those willing to are tested to embark on second or third Trainer Journeys of their own.