Following on from Pal Park in Generation IV, Black and White allow you to transfer - rather than trade - your old Pokémon onto your new game. Rather than Pal Park, this is now done using a device called the PokéShifter.

The PokéTransfer Building is located on Route 15 (Unova) (just east of Marvelous Bridge) and is accessible as soon as you've defeated the Pokémon League. This time in order to do the transfer you will require 2 DS's. Afterall, there aren't 2 DS cart slots on one DS (now there's a thought Nintendo...). Simply go to the PokéShifter building on your Black/White game and activate the PokéTransfer. This will send out a DS Download Play invitation for you to find and accept on the second DS, and from there the game will talk you through the relevant steps.

Just like how Pal Park worked, you will be able to send over 6 Pokémon at a time. However, there is no limit as to how many times you can do this in a single day. Additionally, rather than roaming around attempting to find them, you get to capture them back in a fun mini-game.

On your top screen are several patches of grass and your Pokémon will be seen jumping inbetween patches and hiding in them. Using the crossbow on the bottom screen, you have to fire Pokéballs onto the top screen and hit your Pokémon with them. Hitting a Pokémon with a Pokéball will successfully recapture the Pokémon. There is also a time limit to this, so there's no time for feeling sorry for your Pokémon here. This is business. Rarer Pokémon will tend to move faster, hence making them trickier to recapture.