Fall Meeting of the Southern California Petroleum Section of AIME, 17–18 October, Los Angeles, California Abstract A new cement-in-oil slurry has been developed which has proven itself in the field to be an efficient and valuable aid in helping to reduce or eliminate water production in oil and gas wells. The new slurry utilizes a viscous and thixotropic, kerosene-based carrying agent possessing a low fluid loss, which will suspend and carry the cement particles to maximum depths in the formation at comparatively low injection pressures. The carrying agent places a protective coating of viscous oil around the cement particles and retards the wetting of the cement until all of the slurry has had time to be placed in the formation. After a certain time interval, special chemicals contained in the slurry cause the viscous oil to be reverted to thin kerosene and also will permit the cement particles to become water wet and thereby set the cement. Any slurry entering the oil bearing portion of the formation and contacting no water will be recovered as thin kerosene and unset cement. Introduction Although no statistics are available, it is well known by engineers and other production personnel that present methods of squeeze cementing are not completely satisfactory. Unsatisfactory results have been the rule rather than the exception in many areas when squeezing becomes necessary. Problems that can arise are numerous: failure to displace the desired amount of slurry out of the tubing at an allowable pressure; difficulty in regaining oil production after squeezing; frequent reversion to the original water production when stimulation is necessary after squeezing.