Through a series of complex processes, under the umbrella term of neurovascular coupling, neuronal activity ultimately manifests as a signal change in an MR image via the blood-oxygenation level dependent (BOLD) contrast. Functional MRI (fMRI) capitalises on this contrast mechanism to infer neuronal activity from BOLD contrast variation in a time series, typically acquired while the participant engages in a task. This approach has proved valuable in furthering our understanding of the working of the human brain. Here, issues pertinent to acquiring data with sufficiently high sensitivity to detect such changes are considered, e.g. susceptibility effects, physiological noise and approaches facilitating high spatio-temporal resolution.