日本民法百年中的债法总论和契约法

The Obligation to pay attention to safety and the Law regarding Property and Land Lease are new issues arising from general princi ples of Japanese Obligation Law and Contract Law.How to define application of ob ligation to pay attention to safety within contract law and other issues not onl y have significance in theoretical studies,but also have practical implications. The Law regarding Property and Land Lease provides amendment to the so-called do ctrine of“sale breaking up lease”,with a view to protection of the vulnerable ,those without ownership.The article explores in more in-depth way the two issue s through examination of cases and doctrines,and introduces discussions on direc tion of development of obligation law in circles of civil law in Japan.