Integrated Water Resources Planning and Management (IWRPM) is a participatory system with all of stakeholders and decision-makers; which is defined as a way for sustainable development of water resources considering all of surface and ground water resources in quality and quantity parts and all of demands such as municipal, industrial, agricultural and environmental demands. The Zayandehrud River Basin is one of the most important watersheds in central Iran; and is a crucial source of water for irrigation, as well as for industries, animal farming, municipal supply and wastewater dilution; which is an ideal case study for IWRM studies. Its location in two provinces of Iran, inter-basin water transfer, different hydrological and climatic conditions, surface and ground water interaction and conjunctive use of them, lenty demand sites with different demands are the reasons of that this basin is known as a complex water system. This study investigates the approaches to reach and apply IWRPM goals in the Zayandehrud basin regarding its conditions, available data and information assuming the quantity part of IWRM studies is more important than quality part. The goals of this study are development of a planning model for the Zayandehrud basin and scenario analysis of four developed scenarios. Those are baseline (Trend), supply management, demand management and meta (supply and demand management) scenarios. Five performance criteria, the time-based and volumetric reliability, resilience, vulnerability and maximum deficit are used for scenario analysis and evaluation. One index, the Water Resources Sustainability Index is used to summarize the performance criteria and to facilitate comparison among trade-offs. A full recognition of the basin and surveying of demands and water resources, creation of a data and information base, selection of suitable tools for modeling, development of planning model, calibration and verification of it are the most important and time-consuming stages of this research. The planning model for the Zayandehrud basin was built to evaluate all scenarios. The period of hydrologic analysis is 21 years, (from Oct/1991 to Sep/2011); and the Zayandehrud model was calibrated for 17 years and validated for 4 years using a Historic scenario that considered historic water supply, infrastructure and hydrologic conditions. This period of analysis contains the historical record of the water abundant period of 1992-1995, the drought period of 2001-2003 and part of the most recent drought of the years 2008-2011. Informational uncertainties arising from historical data, management policies, rainfall-runoff model, resources preferences, demands priorities and sustainability index are considered in a conceptual framework and considered in the modeling process with appropriate methods. Based on the Incremental Flows (IFs) method, the Zayandehrud basin conditions and allocation module features in WEAP, a method is roposed to calculate the interaction between river and aquifers. Comparison of results of this method with others shows that this method is an appropriate and effective method. In this study, fuzzy time-based reliability, fuzzy resilience and fuzzy vulnerability (RRV-Fuzzy) are developed to evaluate the real performance of systems. High performance of these criteria compared with previous approach (RRV-Fixed) are shown through a theoretical example. Also, by fuzzified erformance criteria, the fuzzy sustainability index is estimated by fuzzy sets theory. Then, scenarios are developed for the near future (from Oct/2015 to Sep/2019) considering climate change conditions (scenario A2) and precipitation and temperature data . Because the Zayandehrud model is a planning model and not a hydrologic model (rainfall-runoff model), an Adaptive Network-based Fuzzy Inference System (ANFIS) is used to generate synthetic natural flows considering temperature and precipitation as inputs. After uploading data to the Zayandehrud model, results are evaluated by fuzzy performance criteria and sustainability index. Results for the Baseline scenario show that water demands will be supplied at the cost of depletion of surface and groundwater resources, making this scenario undesirable, unsustainable and with the potential of irreversible negative impact in water resources. Hence, the current water management policy is not viable. The Supply Management scenario may be used to improve demands supply but it have not a tangible effect on resources.