Family Fabaceae dominates the plant world and consists of a large number of plants which are having Ayurvedic medicinal importance. This family Fabaceae consists of 600 genera with 12000 species and are arranged in three well defined sub families and they are Papilionaceae, Caesalpiniaceae and Mimosaceae. The sub family Papilionaceae consists of 400 genera with 7000 species. The sub family Caesalpiniaceae consists of 56 genera with 650 species. The sub family Mimosaceae consists of 23 genera with 550 species. A large number of crude drugs are reported in Ayurveda system of medicines based on plant source (Anonymous: 1952, Anonymous: 1986). According to current estimate nearly ¾ of the drugs is used for curing human ailments in India are of plant origin (Mitra and Jain, 1991). As many as 3226 out of 4752 communities in India representing 70% of the population are dependent on the traditional plant based medicines (Gadgil and Rao, 1993). The tribal communities use over 500 species of plants for medicinal purposes (Pushpagadan, 1994). Total herbal medicines have became an important and crucial area of research due to its non side effects and health care. A large number of crude drugs are reported in Ayurvedic system based on plant sources (Anonymous 1952, 1986). The history of medicinal plant is intimately connected with the history of botany. Primitive man lived at the mercy of nature, in constant terror of diseases. A large number of plants provide a source of important crude drugs in traditional medicinal system in different parts of globe. Records of every civilization throughout the world reveal that a considerable number of drugs used in modern medicine were in use even in ancient time (Chopra and Handa, 1961). No authentic records of any kind except a few archaeological sculpture of Mohan-jo-Daro are available from the pre Vedic period in this century. But Rig and Atharvaveda, which date back to 2000 to 1000 B.C. and which are our oldest Vedic literature resources, contain valuable information regarding medicinal plants of that period (Anonymous, 1962,1963). Ayurvedic drugs with their two different actions may nicely be compared with the pharmaco-dynamic and chemo-therapeutic remedies respectively of the modern medicines . Modern pharmacology being compartmental in nature i.e. organ and tissue-wise evaluation of drugs, mostly done through animal experiments and on the basis of physiological responses to them, with an idea of finding out a comparision or corelation of it with Ayurvedic pharmacotherapeutics. Contemporary drugs of modern medicine, pharmacologically developed and accepted in the therapeutics, act in a limited manner. Of late, some of the modern medicinal scientists have realized the importance of Ayurvedic concepts. Thus, Rienacker in his article “The future of medicines” says a new type of medicinal scientist are appearing on the scene who no longer regard diseases mechanically as local phenomena but as symptoms resulting from a general state of disorganizations and disharmony (Weiss, and Fintelmann, 2000). Sickness has been man’s heritage from the beginning of his existence and the search for remedies to combat it is perhaps equally old. Therefore, man has utilized the plant around him as prophylactic or therapeutic aids to health. The world’s oldest pharmacological or therapeutics writing comes from India and China but fairly large Indian population depends even at the present time on indigenous system of medicines such as Ayurveda , Unani and Siddha . Untill 19th century, Botany and Medicine were practiced as interrelated art when they emerged as two distinct sciences (Leyel, 1974) . But in the recent times both these have been once again drawn together with the revival of herbal remedies and the growing curiosity about folk and native medicine and their possible scientific basis. The significance of herbal medicines is shown by the fact that according to surveys in 1960, nearly half of all prescriptions filed in U.S.A. contained one or more active ingredients of natural origin (Gosslein, 1962; Farnsworth, 1969). In addition, contrary to general opinion of natural origin has also increased in the recent years. Schultes (1963) rightly stated that our challenge is to salvage some of the modern medico-botanicallore before it becomes for ever entombed with the cultures that give it birth. Kirtikar and Basu (1935) stated that the only way to illumine the whole field of native therapeutics is to survey it in small tracts and sift the value of those drugs peculiar to each provides in every country . There is a wide feeling that there is beneficience in the scheme of nature which provides in every country, suitable remedies on the spot of the ill to which humanity is locally most prone. Very little has been done so far to incorporate in the practise of physicians in the country the medicines which in India nature scatters broadcast from her lap. Plants have been one of the most important source of medicines ever since from the dawn of human civilization. Approximately one-third of all the pharmaceuticals are of plant origin. The medicinal value of medicinal plants is due to the presence of specific chemical substances present in them which when consumed in small doses produce physiological action in the human body . Chemically the plant may have alkaloids, steroids, glycosides, essential oils, dyes, tannins, lattices, vegetable oils and many other groups of compounds which may have marked pharmaceutical action such as antimalarial, anticancerous, antidiavetic, antihelmintic, antidysentric. Indian system of medicine is more and permanently effective than Allopathic medicines. Many patients suffering from chronic disease are abandoned as hopeless in Allopathic treatment have found a salve in Indian system of medicine. India has an impressive medicinal heritage which encompasses various system of medicines viz Ayurveda, Siddha, Yunani and all the tribal system of medicine. It may be concluded that a large number of crude drugs are available in the Ayurvedic system of medicine which can be employed for the cure of diseases. These crude drugs are easily available from the locally growing plants and donot have any side effects. A large number of rural poor people can benefit from these crude drugs of simple nature. However, detailed investigation on pharmacognostical characterization of these crude drugs are needed to make their effective application possible (Mooss 1953, Raghunathan and Mitra 1982, Rastogi and Mehrotra 1991, Sengupta 1984). Though we are living in the age of synthetic drugs today, the uses of crude drugs or Ayurvedic medicines are increasing day by day because due to the cost of Allopathic drugs and the treatment procedures they remain beyond the reach of village people. Secondly these drugs are not only expensive but also have some undesirable side effects. That is why a vast multitude living in the villages especially the backward class, tribals and the poor people solely depends on the Ayurvedic medicines or local medicines from the plants. Today herbal drugs are gaining importance again despite of tremendous revolution in the contemporary drug development. Every country has to work out appropriate strategies. The market for herbal drugs is growing fast because they have no side effect and they are comparatively less expensive. Secondly these drugs are effective against many chronic diseases like cancer and these drugs are found to be permanent cure for several diseases like respiratory disease, diabetes. Another significant property of the herbal drug is that, it can be useful against several ailments in different combinations. In one combination it has one medicinal effect while in the other, it has other effect. Due to modernization and inability of world population to use the products of western pharmaceuticals, the self made Ayurvedic physicians have to depends mainly upon the use of traditional medicines and the people have to depends on the market supply of crude drugs. Due to the lack of complete knowledge about the drugs, crude drugs available in the market are adulterated and so that no desirable effect of the medicine is obtained which leads to the disappointment of physician as well as patient and this discredits Ayurvedic medicines. Some of such adulterated drugs available in the market are given below. The Tinnevelly senna is found to be adulterated with Palthe senna (Cassia auriculata). In commerce the Arabian samples of senna have been to found mixed with stem, midribs, dirt and the leaflets and pods of Cassia auriculata and C.holosericia Fresen., reported to have been introduced into India, C.italica and C.montana; the mature leaves of C.tora are also sometimes used as adulterants . Others are Ailanthus altissima (Mill.) Swingle , Colutea arborescens Linn. and Globularia alypum Linn. The leaflets of Coriaria myrtifolia Linn., Solenostemma argel Hayne, Tephrosia apollinea DC. and T. purpurea Pers. have been detected in commercial samples, and reported to be poisonous. The senna pods of Arabian origin are sometimes substituted by those of Cassia fistula, C.grandis, C.italica and C.moschata H.B.and K. In the course of time, socio-economic changes and rapid deforestation have made the self contained Ayurvedic physicians to depend on pharmaceutical houses. So the physicians have no means to ascertain the authenticity of medicines. The crude and prepared medicines available in the market may be Adulterated or replaced by cheap and worthless substitutes . In order to overcome this problem, correct identification of crude drugs pharmacognosy, pharmacological and ethnobotanical characterization is necessary. There is a need of concerted efforts for the characterization of crude drugs. The investigation about detailed anatomical and morphological properties of these crude drugs shall be undertaken for the further investigation. Investigations in the field of pharmacognosy and pharmacology can supply valuable information on medicinal plants with regard to their availability, botanical properties, methods of cultivation, collection, storage, commerce and therapeutic uses (Kumar, 1992). It may be concluded that there is immense potential for new and unexploited plant material which may yield new and potential crude drugs.