Working between two networks

[TriedandTested]

We have a member of staff here with a laptop..she works between two sites a lot. Her laptop is currently set up to operate on one network, but i would like her to be able to simply come to the other site, plug in and access this network. I understand that setting up trusts between the servers is one way of doing it, but i dont have much experience doing that and was hoping there was an easier way or this that the only option?

I basically want her to have the options of the two domains on the login screen.

Thanks.

 

[v_odd]

would it not work to give her an alternate static ip address in the connection properties and have her log in on the one domain, if it didnt find the dhcp server it would then give her the static address