Two-dimensional speckle tracking echocardiography (2D-STE) enables assessment of left atrial (LA) function with better reproducibility and less load dependence than those with conventional methods. Data regarding LA functions determined by 2D-STE in patients with various cardiovascular diseases have recently been accumulating. LA strain has emerged as a novel parameter with the potential of improving the diagnostic accuracy of left ventricular diastolic dysfunction and the prognostic value in patients with heart failure and stroke. Furthermore, LA dysfunction determined by 2D STE can provide incremental prognostic information to conventional echocardiographic parameters in patients with cardiovascular diseases. Hence, 2D-STE appears to be a promising technique for diagnosis and therapeutic decision-making. Data regarding LA functions determined by three-dimensional speckle tracking echocardiography (3D-STE) have also been accumulating. Here, I review recent studies, especially those published after 2016, on clinical applications of LA function assessed by 2D-STE and 3D-STE and summarize the remaining problems to be solved for improving the clinical utility of these techniques.