We use MasterCode to perform a frequentist analysis of the constraints on a phenomenological MSSM model with 11 parameters, the pMSSM11, including constraints from sim 36/fb of LHC data at 13 TeV and PICO, XENON1T and PandaX-II searches for dark matter scattering, as well as previous accelerator and astrophysical measurements, presenting fits both with and without the (g-2)_mu constraint. The pMSSM11 is specified by the following parameters: 3 gaugino masses M_{1,2,3}, a common mass for the first-and second-generation squarks m_{tilde{q}} and a distinct third-generation squark mass m_{tilde{q}_3}, a common mass for the first-and second-generation sleptons m_{tilde{ell }} and a distinct third-generation slepton mass m_{tilde{tau }}, a common trilinear mixing parameter A, the Higgs mixing parameter mu , the pseudoscalar Higgs mass M_A and tan beta . In the fit including (g-2)_mu , a Bino-like tilde{chi }^0_{1} is preferred, whereas a Higgsino-like tilde{chi }^0_{1} is mildly favoured when the (g-2)_mu constraint is dropped. We identify the mechanisms that operate in different regions of the pMSSM11 parameter space to bring the relic density of the lightest neutralino, tilde{chi }^0_{1}, into the range indicated by cosmological data. In the fit including (g-2)_mu , coannihilations with tilde{chi }^0_{2} and the Wino-like tilde{chi }^pm _{1} or with nearly-degenerate first- and second-generation sleptons are active, whereas coannihilations with the tilde{chi }^0_{2} and the Higgsino-like tilde{chi }^pm _{1} or with first- and second-generation squarks may be important when the (g-2)_mu constraint is dropped. In the two cases, we present chi ^2 functions in two-dimensional mass planes as well as their one-dimensional profile projections and best-fit spectra. Prospects remain for discovering strongly-interacting sparticles at the LHC, in both the scenarios with and without the (g-2)_mu constraint, as well as for discovering electroweakly-interacting sparticles at a future linear e^+ e^- collider such as the ILC or CLIC.