Note - This facility is present in Pokemon-6, though most of the information within is also applicable to Pokemon-1 and other derivatives. This exact facility does not exist in canon Pokemon, though in almost all canon Pokemon continuities, an analogous facility of various levels of importance and influence is run by Professor Oak.
Pallet Town Pokemon Research Laboratory is a United States government facility under the care of both the military and civilian government. It is primarily used for Pokemon research of all kinds and is one of the foremost facilities on the planet.
Locals informally refer to this as "Oak's Lab", or "Oak Labs", after its most famous researcher and current head, Professor Samuel Oak, inventor of the Pokedex.
The Labs were founded around the time of Pallet Town's founding in the 1950's to study the unusual effects of Pokemon linking and the top-secret knowledge of the unusual effects the Pokemon Islands had had on those who were on the islands during World War II, which had prevented the Japanese from seizing the island due to the intervention of the now-powerful civilian population. As it was uncovered that intense exposure to threats - and the subsequent practice and Pokemon psionic linking that occurred afterwards - bolstered their overall capabilities and that of their Pokemon tremendously, it was viewed as utterly urgent that this be studied but kept under wraps, a process which took decades and continues to this day. It also came to double as a Cold War-era backup bunker with independent backup control over several missile silo complexes located throughout the Pokemon Islands.
The Labs truly came to attention during the 1970s when Vietnam veteran and prodigy Samuel Oak was assigned as a marine lieutenant after a tour of duty fighting the Viet Cong. Though undiscovered until now, he quickly seized on the recently developed optical transistor to create a unique sensory system and apparatus known as the Pokedex, which hosted a small-scale, hyper-fast (for then) computer unit capable of cataloging, scanning and tracking Pokemon of all sorts, as well as being a considerable information storage and processing device. This demonstrated his considerable knowledge of most engineering and biological aspects, eventually leading to him earning several honorary doctorates. The title "Professor", strictly speaking, is honorary, though he is one of the most respected Pokemon researchers in the world, and a respected engineer and scientist in most other respects with knowledge and expertise far outside of his core area.
In addition to its military duties, the lab has also served as an education center for the civilian population, carrying on the tradition of "Pokemon Professors," who had traditionally taught young trainers in how to handle Pokemon. It still serves in this function today and is well known for its considerable starters, including a champion-quality line of Bulbasaurs hand-raised by Oak himself. A wide variety of Pokemon are available for new trainers, though the most common choices are Bulbasaur, Charmander, Squirtle, Eevee, and in some cases a member of the Pikachu line after Ash managed to popularize them.
It is from this aspect that the labs became a major military facility. Realizing that his old student, Giovanni, had uncovered the secrets of the power of the trainers in the Pokemon Islands, he watched Team Rocket rising out of the Rocket Gang very carefully. Ultimately he came to the correct conclusion that his power hungry pupil was attempting to force the youth of the Pokemon Islands, who had been exposed to their environment nearly their entire lives (and thus benefiting from it as Pokemon trainers and fighters since birth), to become his own personal army. Failing that, the criminal activities of the organization alone were plenty to give him a massive bolster his own organization's power. He had also gone to lengths to ensure the government could not properly intervene, from the usage of obscure laws preventing military usage on United States soil as well as having his tentacles in all aspects of the local government to cripple the police system, he was slowly pervading any real response that could be done in the realm of conventional and legal remedies. As such, fighting fire with fire, he gathered the most powerful and capable of the teenagers in the area, most of whom were already fighting Team Rocket independently, forming Oak's Trainers. Using his own considerable funds as well as those from quiet backing from the US Marine Corps, he gave them some organization and coordination as well as the resources to fall back on, and a way to coordinate their fights against Team Rocket.
A somewhat controversial aspect of the Labs is their power core. Not using civilian energy sources, it instead uses a highly experimental fusion reactor source. Installed only a few years before Unification, against Professor Oak's wishes, it caused considerable concern to the local population when its existence was leaked to the population. However, upon Unification an analysis confirmed that the design was both useful and safe. However, an undocumented "feature" is that of a considerable self-destruct system. Though normally kept under tight lock and key, it can be deliberately overloaded to create a nuclear detonation. Only a few people have the knowledge and access codes to be able to do this, and it is impossible to activate independently. Its design is virtually tamper-proof; the core would be rendered useless long before a malfeasor would be able to detonate it, though tampering effects can cause the system to fail outright which is a problem in and of itself.
In recent years since the Team Rocket threat, and the advent of Oak's trainer team, the labs have gone through a substantial number of modifications. Although previously built to house a Cold War era backup bunker, it now has state-of-the-art defensive systems, including a number of weapons systems, retractable armor, and forcefield systems in addition to backup power to augment its already considerable central power generation system. One item of note is that the missile complexes once linked to its bunker section are now completely severed from its control. The bunker level has instead been turned into a command center for operations of Oak's trainer team throughout the islands and beyond.
Scientific facilities in the labs include a complete suite of laboratories and support systems. Nearly any kind of Pokemon research can be conducted there, and a large group of Pokemon are available to conduct experiments with (in a strictly non-harmful manner). There are also electrical engineering labs, and a few power system labs, and quite notably a microbiology lab which is dedicated to the study of pathogens, particularly the so-called "Pokemon rabies" which has afflicted the Pokemon population of the Pokemon-6 world. Included in this collection of tools is a full biological containment system that can convert nearly the entire building into a "clean room" or isolation area for research into extremely virulent diseases. The Labs hosts a supercomputing cluster which manages much of the building's facilities, and has a large amount of dedicated processing power for lab experiments.
In terms of more mundane facilities, Oak Labs has a small medical center and Pokemon Center staffed by at least one doctor and one dedicated Nurse Joy. Food services are available as well as limited "social" areas for his trainer team. Bunks are also available, including a few semi-permanent and permanent bunks for those members who have distant homes and are staying nearby for the moment, have no place else to go, or are orphaned. These bunks are also used to house some of the many Marines which guard the facility, a number that has only gone up in recent years to protect the invaluable research within.