At the XXIX IAU General Assembly held in Honolulu from 3–14 August 2015, the meetings known as Special Sessions and Joint Discussions were replaced by new 'Focus Meetings'. Astronomy in Focus XXIXA presents the most relevant contributions from the Focus Meetings together with summaries of all the accepted papers and posters. It covers the meetings on the following areas: dynamical problems in extrasolar planet science; astronomical heritage; scholarly publishing in astronomy; statistics and exoplanets; the exploration of small worlds; ground and space astrophysics and heliophysics; laboratory astrophysics; brightness variations of the Sun and Sun-like stars; astronomy for development; and mitigating the threats of light pollution and radio frequency interference. The publications Astronomy in Focus XXIXA (together with its companion, XXIXB), the proceedings of the six main Scientific Symposia and Reports on Astronomy: Commission Legacy Reports, fully cover the XXIX IAU General Assembly.