Cheese is believed to be the oldest of the dairy products and the first form in which milk was preserved for future use. One may conjecture that it owes its origin to the accidental storing and ripening of sour milk curd. Although it has been a staple food with many races for uncounted years, there is a widespread belief that it is suitable for use chiefly in small quantities as an accessory to the diet, and that in large quantities it is likely to produce physiological disturbances. We are inclined, therefore, to think of those who make cheese one of the chief articles of their diet as being driven to this course by necessity rather than being led to it by choice. Because of these opinions extensive studies have been carried on as a part of the Department Work in Home Economics, of the food value, thoroughness of digestibility, ease of digestion, physiological effect, and special character of cheese as food as well as of methods which are followed in preparing it for the table. The conclusion drawn from this extended study is, in brief, that cheese properly prepared and used is not generally a cause of physiological disturbances, and that it may easily be introduced into the bill of fare in such quantities as to serve as the chief source of nitrogenous food and may be made a substitute for other nitrogenous foods when such substitution is desired.[1] The results of these studies have been brought together in this bulletin with a view to making them helpful to all interested in the subject, but particularly to housekeepers. From the standpoint of the housekeeper, cheese is of importance because of its high nutritive value, particularly its high percentage of protein or muscle-forming materials, because of the ease with which it can be kept and prepared for the table, and because of its appetizing flavor and of the great variety of ways in which it can be served. From the point of view of agriculture cheese is an important commodity. The latest census figures available show that considerably over 300,000,000 pounds are made yearly in the United States, the value of the product being nearly $29,000,000, and the amount of money invested being over $6,000,000. The figures quoted are from the census report which first separated the details of the cheese industry from those of the butter and condensed-milk industries. From earlier statistics available, however, it is fair to judge in a general way of the development of any one of these industries from the figures given for the three industries combined. In general, these figures show that there was a great leap forward in the three industries in the decade between the years 1880 and 1890, and that since that time there has been a continuous, steady, healthy growth in the business of cheese making.