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As we enter a golden age for studies of internal kinematics and dynamics ofGalactic globular clusters (GCs), it is timely to assess the performance ofmodelling techniques in recovering the mass, mass profile, and other dynamicalproperties of GCs. Here, we compare different mass-modelling techniques(distribution-function (DF)-based models, Jeans models, and a grid of N-bodymodels) by applying them to mock observations from a star-by-star N-bodysimulation of the GC M 4 by Heggie. The mocks mimic existing and anticipateddata for GCs: surface brightness or number density profiles, local stellar massfunctions, line-of-sight velocities, and Hubble Space Telescope- and Gaia-likeproper motions. We discuss the successes and limitations of the methods. Wefind that multimass DF-based models, Jeans, and N-body models provide moreaccurate mass profiles compared to single-mass DF-based models. We highlightcomplications in fitting the kinematics in the outskirts due to energeticallyunbound stars associated with the cluster ("potential escapers", not capturedby truncated DF models nor by N-body models of clusters in isolation), whichcan be avoided with DF-based models including potential escapers, or with Jeansmodels. We discuss ways to account for mass segregation. For example,three-component DF-based models with freedom in their mass function are asimple alternative to avoid the biases of single-mass models (whichsystematically underestimate the total mass, half-mass radius, and centraldensity), while more realistic multimass DF-based models with freedom in theremnant content represent a promising avenue to infer the total mass and themass function of remnants.

Mass modelling globular clusters in the Gaia era: a method comparison using mock data from an $N$-body simulation of M4