Galactic dynamics is fundamental to understanding the formation of galaxies, their internal evolution and their current structure. It also governs interactions between galaxies in systems ranging in size from groups to large clusters of galaxies. While galactic dynamics has traditionally focused on the evolution of the stellar components of galaxies, studies over the past two decades have shown that all aspects of galaxy evolution: star formation, the nature and distribution of stellar populations and the chemical evolution of a galaxy as a whole are strongly influenced by the interplay between the dynamics of stars, gas, and dark matter.

The last major conference on Galaxy Dynamics was held in St. Petersburg in 2007. Since then there has been a divergence in the dynamical methods employed to understand the Milky Way where 3D kinematics of resolved stellar populations are becoming available, but observed from our helio-centric perspective, and the dynamical methods employed in the study of external galaxies where wide field line-of-sight kinematics are available for large samples of galaxies. Two primary aims of the proposed Symposium are to bring together these diverging communities to ensure that (1) our detailed understanding of the Milky Way and other Local Group galaxies informs our understanding of distant galaxies, their formation and evolution, and (2) the comparison of the Local Group galaxies with external galaxies in turn informs our understanding of the formation and evolution of the Local Group in a cosmological context.

Galaxies in the Local Group have seen the largest increase in high quality resolved data resulting in a substantial revision in our understanding of both the structures of the individual galaxies and the dynamical interactions between them. Major photometric and spectroscopic surveys such as 2MASS, SDSS, RAVE, PanSTARRS, LAMOST, BRAVA, ARGOS, VVV, APOGEE, DES etc. have yielded new insights into the formation history and the structure of Milky Way including the structure and stellar populations of the Galactic bar/bulge, the thin and thick disks, and the stellar halo. In particular we expect significant impact from chemo-dynamical studies of the thin and thick disks from cross correlations of astrometric surveys with spectroscopic surveys. In addition, on-going surveys of the Milky Way bar/bulge have led to a dramatic revision in our understanding of the central regions of our Galaxy. HI surveys of nearby galaxies (e.g. ALFALFA, THINGS, LittleTHINGS) have had a great impact on our understanding of the role of gas in galaxy evolution. Large photometric surveys have uncovered dozens of new dwarf galaxies. Simultaneously, large samples of radial velocities for stars in these dwarf galaxies have led to the discovery that many of them may be dark matter dominated (or alternatively the kinematics could be signaling a failure of Newtonian mechanics on weak acceleration scales). Proper motion surveys of Local Group members with the HST have yielded the 3-dimensional motions of many members of the Local Group. Ground based and space based imaging surveys of the Magellanic clouds and M31 (PHAT, PAndAS, SPLASH etc.) have mapped their stellar populations and radial velocities of many stars in exquisite detail. These data will soon be surpassed by the vast multi-dimensional data sets that will be available from Gaia and eventually JWST, WFIRST and LSST.

Alongside these developments in our understanding of the very local Universe, there have been significant advances in theoretical understanding of the internal structure and evolution of spiral and elliptical galaxies. From an observational viewpoint there is evidence corroborating the secular evolution scenario. However, it is not yet clear what the relative roles of internal secular evolution and environmental effects are in the cosmological context. It has become clear that bars and spirals drive substantial secular evolution in disk galaxies, though there are still unsolved questions regarding the mechanisms. These structures also transport angular momentum from the inner to the outer disk, scatter stars away from circular orbits contributing to the well-established age-velocity dispersion relation, cause radial migration of stars, smooth rotation curves and disk density profiles, and influence the chemo-dynamical structure of stellar disks. Thus, the present-day properties of disk galaxies are not simply determined by their formation history. Large integral field spectroscopic surveys of external galaxies like SAURON, ATLAS3D, SAMI, CALIFA and MaNGA have resulted in dramatic advances in our understanding of the dynamical structure and formation history of elliptical and spiral galaxies. Despite substantial recent progress, important questions remain about Program outline: the role of interactions, gas, and feedback in the evolution and transformation of these systems. In addition, deep imaging spectroscopy with IFS like SINFONI and KMOS now enables us to directly probe the dynamical properties of early disk galaxies at high redshift, and JWST will further revolutionize this field.

It is our hope that the proposed Symposium will provide an important and timely platform to discuss and share ideas on the applications of galactic dynamics to the Milky Way and external galaxies.

Key topics include:

- The structure, dynamics, and assembly history of the Milky Way galaxy

- Dynamical evolution of the Local Group and its members (including M31, the Magellanic clouds, dwarf spheroidal galaxies)

- Dynamical influence of internal secular evolution vs. mergers and tidal interactions on galaxy evolution

- Dynamics of disk galaxies: the influence of spiral structure, radial migration and bars

- The role of gas in the dynamical evolution of galaxies

- Dynamical modelling of galaxies to measure the mass profiles of baryons and dark matter halos and central supermassive black holes using large IFS surveys

- Dynamics of galactic nuclei and nuclear star clusters

- Nonlinear and orbital dynamics: impact on galaxy evolution