When working on stairs, the best articulated ladder configuration to use is the step or stair mode (also called staircase configuration). This setup allows the ladder to adapt to the uneven surfaces and angles of stairs, providing stability and safety while working. Articulated ladders with independently adjustable legs are especially suitable because they can be configured to step ladders for stairs, ensuring the ladder is level despite the stair height difference between the legs. It is important to always follow manufacturer guidelines and secure the ladder properly to prevent slipping or tipping.