the wellbore for the sliding sleeve technique is different in that the sliding sleeves are included at set spacings in the steel casing at the time it is set in place. the sliding sleeves are usually all closed at this time. when the well is due to be fractured, the bottom sliding sleeve is opened using one of several activation techniques and the first stage gets pumped. once finished, the next sleeve is opened, concurrently isolating the previous stage, and the process repeats. for the sliding sleeve method, wireline is usually not required.