Filter theory was proposed Kerckhoff and Davies, this is the process by which we choose romantic partners using a series of filters. These filters narrow down a suitable partner. This theory suggest that different filters are used at different stages in partner selection. The first filter in the selection process is social demography this includes age and location. You find someone more attractive when you have more things in common so if your similar ages you feel a stronger connection, this usually occurs during the courtship stage. The second filter stage is having similar attitudes, having similar attitudes like values or beliefs means communication is easier so the relationship is more likely to continue. This usually occurs when looking for a long-term partner. The last stage of the filter theory is how complementary the couple is. This means how the couple meet each other’s needs within the relationship, this is the most important factor when establishing a long-term partner.