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PSR J0218$+$4232 is a millisecond pulsar (MSP) with a flux density $\sim$ 0.9mJy at 1.4 GHz. It is very bright in the high-energy X-ray and $\gamma$-raydomains. We conducted an astrometric program using the European VLBI Network(EVN) at 1.6 GHz to measure its proper motion and parallax. A model-independentdistance would also help constrain its $\gamma$-ray luminosity. We achieved adetection of signal-to-noise ratio S/N > 37 for the weak pulsar in all fiveepochs. Using an extragalactic radio source lying 20 arcmin away from thepulsar, we estimate the pulsar's proper motion to be$\mu_{\alpha}\cos\delta=5.35\pm0.05$ mas yr$^{-1}$ and $\mu_{\delta}=-3.74\pm0.12$ mas yr$^{-1}$, and a parallax of $\pi=0.16\pm0.09$ mas. The very longbaseline interferometry (VLBI) proper motion has significantly improved uponthe estimates from long-term pulsar timing observations. The VLBI parallaxprovides the first model-independent distance constraints:$d=6.3^{+8.0}_{-2.3}$ kpc, with a corresponding $3\sigma$ lower-limit of$d=2.3$ kpc. This is the first pulsar trigonometric parallax measurement basedsolely on EVN observations. Using the derived distance, we believe that PSRJ0218$+$4232 is the most energetic $\gamma$-ray MSP known to date. Theluminosity based on even our 3$\sigma$ lower-limit distance is high enough topose challenges to the conventional outer gap and slot gap models.

Very Long Baseline Interferometry Measured Proper Motion and Parallax of the $\gamma$-ray Millisecond Pulsar PSR J0218+4232