Although information workers may complain about meetings,
they are an essential part of their work life. Consequently,
busy people spend a significant amount of time scheduling
meetings. We present Calendar.help, a system that provides
fast, efficient scheduling through structured workflows. Users
interact with the system via email, delegating their scheduling
needs to the system as if it were a human personal assistant.
Common scheduling scenarios are broken down using well defined
workflows and completed as a series of microtasks that
are automated when possible and executed by a human otherwise.
Unusual scenarios fall back to a trained human assistant
who executes them as unstructured macrotasks. We describe
the iterative approach we used to develop Calendar.help, and
share the lessons learned from scheduling thousands of meetings
during a year of real-world deployments. Our findings
provide insight into how complex information tasks can be
broken down into repeatable components that can be executed
efficiently to improve productivity.