A fencing/railing assembly adapted to be positioned between a pair of posts and mounted thereto. The assembly includes a plurality of pickets, a plurality of rails extending transverse to the pickets, and one or more pivoting, sliding connectors for connecting a picket to a rail, with the sliding, pivotal connection concealed by the rail. The connector is slidably mounted to the rail and is pivotally connected to the picket. The sliding, pivotal connection allows the pickets to be oriented at greater angles relative to the rails (i.e. it allows the assembly to rack to a greater degree, thereby allowing the fencing/raining to following more-steeply changing terrain or contours). In one embodiment, an elongated connector strip is concealed by the rail and spans multiple pickets. In another embodiment, the assembly includes a plurality of shorter connectors, one for each picket/rail connection.