An exemplary method includes delivering a cardiac resynchronization therapy using an atrio-ventricular delay parameter and an interventricular delay parameter, measuring an atrio-ventricular conduction delay, measuring an interventricular conduction delay, assessing heart failure and/or cardiac resynchronization therapy performance based at least in part on the measured atrio-ventricular conduction delay and the measured interventricular conduction delay and determining at least one of an atrio-ventricular delay parameter value and an interventricular delay parameter value based at least in part on the measured atrio-ventricular conduction delay and the measured interventricular conduction delay. Other exemplary technologies are also disclosed.