Start with your existing network: ISP==modem==router#1 (may or may not have wifi) You wish to add a second router (perhaps with wifi) like ISP==modem==router#1 ----- router#2 There are two ways to use router#2 isolate all devices on #2 from those on #1 (ie no file sharing) make all devices visible to each other & support file sharing To implement #1; first, find the router#1 LAN address use IPCONFIG and the gateway address shown is the router's address we usually see something like 192.168.X.1 Then, set the router#2 Lan address to X+1, like 192.168.2.1 connect any LAN port on #1 to the WAN slot on #2 and you're done. All devices on router#2 will be able to access the Internet, but nothing on the internet will have access to router#2 and that means if you are hosting some service of game on your system, it will need to be connected to router#1 To implement #2: You need to disable DHCP in router#2 to allow all addresses to be controlled by router#1 connect a pc to any router lan slot login the router using your browser and the router's default address use the default user/password find the router settings disable DHCP save & logout Now disconnect the PC and connect router#1 lan slot to any router#2 lan slot, leaving router#2 WAN slot empty any device on router#1 will be able to ping the devices on router#2 and conversely. WiFi Considerations One tool that is really helpful with WiFi is inSSIDer. This helps finding a channel with the least conflicts in your location. Router#1 (if it has wifi) should be solved first When you add router#2, you can make the SSID similar to that of #1, but add a suffix '2' so you can tell them apart. *IMPORTANT* Make sure that when both routers have WiFi, that they are NOT using the same channels! Otherwise, you're interfering with yourself.