From Bulbapedia, the community-driven Pokémon encyclopedia.
PocketMonsters Fansubs is a fansubbing group subtitling the Japanese Pokémon anime in English. They also own PocketMonsters.net.
The group started subtitling in 2008 with DP094, and they have subbed every core episode from that point and up. Separate translators subtitle earlier episodes, which are released on a irregular schedule.
Names of characters and Pokémon are kept in Japanese, while location names, etc are handled in a way that according to the group best represents the intention of the original name. If the official English games uses a name that works as a straight translation of the Japanese, this name will typically be used by them to lessen confusion. All Pokémon moves use the name from the official English video games.