Procedures employed for the reconstruction of charged particle tracks used by the ATLAS experiment are outlined, and their performance in recent LHC Run 2 data is discussed, with focus on aspects such as the stability with respect to time and instantaneous luminosity, and performance within high-$p_T$ jets. The track-based alignment of the ATLAS Inner Detector is introduced, and its importance to track reconstruction is demonstrated. The current level of understanding of detector deformations affecting track parameter determination is shown, and planned future improvements are outlined. Methods devised to distinguish $b-$ and $c-$quark jets from light-flavour jets are introduced. Techniques to extract and calibrate the performance of these methods on data and Monte Carlo are examined, and their results compared. Finally, forthcoming improvements in these areas are highlighted.