Router configuration problems help!

Hey Guys

I am trying to connect two sites together HQ + remote. The problem i’m having is that i can ping one subnet but not the other. for example i can ping 10.5.2.1 but i can’t ping 10.5.3.1. 10.5.2.1 is the main router i’m trying to get connectivity from router 10.5.3.1 to 10.5.2.1 Can any one point me in the right direction? Thanks in advance

-jmandiaz