A method for placing ball sealers within a well formed within a subterranean formation for sealing holes in a casing of the well is carried out by performing at least one of two operations. The first operation involves providing a tag with at least one ball sealer or a carrier fluid containing the at least one ball sealer to facilitate monitoring of the location of the ball sealer. A tag monitoring device is provided within the well for monitoring the location of the tag. The ball sealer and carrier fluid with the tag are introduced downhole into the well. Information from the monitor device regarding the location of the tag is communicated to a remote monitoring location to the thereby provide an indication of the location of the tag within the well to a surface location. In the second operation a container is provided within the well at a known location downhole within the well. The container contains at least one ball sealer. The ball sealer or sealers are released from the container within the well at the known location in response to an instruction initiated from a surface location.