An electrical connector assembly including an interposer having a side surface and an array of electrical contacts exposed along the side surface. The electrical contacts are located within a contact region that extends along the side surface. The electrical contacts are configured to engage an electronic module mounted over the contact region. The connector assembly also includes a shield wall that is attached to and extends along the side surface. The shield wall separates the contact region into shielded sub-regions. The shield wall includes a conductive material and is electrically coupled to the interposer. At least one electrical contact is located within each shielded sub-region. The shield wall extends between adjacent electrical contacts to shield the adjacent electrical contacts from electromagnetic interference.