  This EPTCS volume contains the proceedings of the 16th Workshop on
Quantitative Aspects of Programming Languages and Systems (QAPL 2019) held in
Prague, Czech Republic, on Sunday 7 April 2019. QAPL 2019 was a satellite event
of the European Joint Conferences on Theory and Practice of Software (ETAPS
2019).
  QAPL focuses on quantitative aspects of computations, which may refer to the
use of physical quantities (time, bandwidth, etc.) as well as mathematical
quantities (e.g., probabilities) for the characterisation of the behaviour and
for determining the properties of systems. Such quantities play a central role
in defining both the model of systems (architecture, language design,
semantics) and the methodologies and tools for the analysis and verification of
system properties. The aim of the QAPL workshop series is to discuss the
explicit use of time and probability and general quantities either directly in
the model or as a tool for the analysis or synthesis of systems.
  The 16th edition of QAPL also focuses on discussing the developments,
challenges and results in this area covered by our workshop in its nearly
20-year history.
