Asthma and pulmonary hypertension involve excessive contractile activity of the smooth muscle of the small airways and arteries within the lungs. While isolated cell studies have provided significant advances in smooth muscle cell physiology, an understanding of how this physiology relates to vessel resistance, requires a preparation that retains the architecture of the pulmonary airways and arteries. One such preparation is the “lung slice”. We have used mouse lung slices to simultaneously investigate the contractile and underlying intracellular calcium ([Ca2 ]i) responses of smooth muscle cells (SMCs) in both intrapulmonary airways and arteries with phase-contrast and confocal microscopy. Lung slices (~100 mm thick) were cut from lungs after filling the alveoli and arteries with agarose and gelatin, respectively. In response to ACH, a sustained contraction of airways was accompanied by a transient increase in [Ca2 ]i followed by Ca2 oscillations. However, the arteries did not respond to ACH. By contrast, 5-HT induced a sustained contraction in both the airways and arteries and a large transient increase in [Ca2 ]i followed by oscillations. In both airways and arteries, in response to either ACH or 5-HT, the frequency of the Ca2 oscillations increased with agonist dose and correlated with increased sustained contraction. The removal of extracellular Ca2 did not block the initiation of contraction or the [Ca2 ]i transients, but did attenuate the Ca2 oscillations and this resulted in relaxation. By contrast, high extracellular K induced transient and unsynchronized contractions of both airway and artery SMCs (twitches) although a greater contraction was observed in arteries. While the [Ca2 ]i responses of both airway and artery SMCs to high K was oscillatory, the frequency of the oscillations were generally slower than those induced by agonists. The removal of extracellular Ca2 or treatment with Ca2 channel blockers prevented contraction and [Ca2 ]i signaling induced by K . In summary, these results imply that a sustained contraction of pulmonary SMCs relies on fast repetitive Ca2 oscillations mediated by Ca2 release from intracellular stores.