The Project Scientist's Discretionary Observing Time is intended for short observing projects for which no approved observing program exists. Proposals for such projects will normally be held for consideration during the next proposal review cycle, however, the Project Scientist may approve Discretionary Observing Time in cases where observation is required by a certain date or where the project's scientific nature dictates urgency. Requests will also be considered when one or two observations are needed to complete an already approved observing program or if a few exploratory observations are needed to demonstrate the feasibility of a new observing program. A proposal for Discretionary Time normally consists of an informal letter describing the proposed observations, scientific objectives, and explaining why discretionary time should be granted in lieu of consideration during the next proposal cycle. Discretionary proposals, like all other requests for observing time, are reviewed by the observatory staff for technical feasibility and spacecraft constraints. An Observation Specification form with target information (see Appendix E), desired exposure times, specific dates for time-critical observations, and so forth, should accompany the proposal for Discretionary Time. Such requests should be sent to the IUE Project Scientist at the address given in Section 5.4.