Vipassana Samadhi                          Samadhi means concentration, or the results of concentration. In the latter sense, some teachers prefer the broader definition, " collectedness". Samadhi is useful in Vipassana but only to the level of momentary concentration.             There are three basic types of concentration:             1) Kanika Samadhi - Momentary concentration.             2) Upacara Samadhi - High concentration, almost to the level of Apana Samadhi.             3) Apana Samadhi - Concentration in which the mind can remain steadfast on one object for long periods.             As noted above, only kanika samadhi (momentary concentration) is necessary for Vipassana practice.              Kanika Samadhi                          The reason we have to use kanika samadhi for Vipassana is that kanika samadhi still remains in the six senses. When changing objects, for example, from sitting rupa to nama hearing (from mind sense to hearing sense), kanika samadhi can follow the change. Kanika samadhi is the basic tool to make Vipassana panna work. It is this changing of objects that allows the yogi to see the rising and falling away of cittas (mental states).             When impermanence is seen in cittas, this impermanence means that cittas are out of control and therefore dukkha and anatta. Upacara samadhi is just one-pointedness, and it cannot be used to see the rising and falling of cittas. When impermanence is realized in cittas, it has to be realized with wisdom, and not samadhi.