The relative magnitude of adjustment in osmotic potential (IY(s)) of water-stressed cotton (Gossypium hirsutum L.) leaves and roots was studied using plants raised in pots of sand or nutrient solution grown in a growth chamber. One, two, and three water-stress cycles were imposed by withholding irrigation from sand-grown plants, or by using PEG-6000 and a special membrane arrangement for solution-grown plants, and the subsequent adjustment in solute potential upon relief of the stress and complete rehydration was followed using thermocouple psychrometers. Both leaves and roots exhibited a substantial adjustment in is in response to water stress, with the roots exhibiting a much larger percentage adjustment. Leaf osmotic potentials were significantly decreased by 20% and 39% with one and three water-stress cycles respectively. Whereas in roots, water stress resulted in comparatively larger percentage osmotic adjustments of 50% and 70% in similar stress cycles. The osmotically adjusted condition of leaves was shown to decrease fairly rapidly after relieving the stress to less than half the initial value within the first few days. The decrease in IY(s) persisted longer in field-grown plants of the same age. The advantage of decreased IY(s) in water-stressed plants was associated with the maintenance of turgor.