this is a lecture note on a groupoid approach to c*-algebras, edited by a. dold and b. eckmann. the author is jean renault, a mathematician from the department of mathematics at the university of orleans. the book is classified under mathematics, with subject codes 22d25, 46l05, 54h15, and 54h20. it was published by springer-verlag in 1980. the book contains an introduction, three chapters, and an appendix. chapter i discusses locally compact groupoids, including definitions, haar systems, quasi-invariant measures, and continuous cycles and skew-products. chapter ii explores the c*-algebra of a groupoid, covering convolution algebras, induced representations, amenable groupoids, r-discrete principal groupoids, and automorphism groups, kms states, and crossed products. chapter iii presents some examples, including approximately-finite groupoids and the groupoids o_n. the appendix discusses the dimension group of the gicar algebra. the book also includes references, a notation index, and a subject index. the work is protected by copyright, and reproduction requires permission from the publisher.this is a lecture note on a groupoid approach to c*-algebras, edited by a. dold and b. eckmann. the author is jean renault, a mathematician from the department of mathematics at the university of orleans. the book is classified under mathematics, with subject codes 22d25, 46l05, 54h15, and 54h20. it was published by springer-verlag in 1980. the book contains an introduction, three chapters, and an appendix. chapter i discusses locally compact groupoids, including definitions, haar systems, quasi-invariant measures, and continuous cycles and skew-products. chapter ii explores the c*-algebra of a groupoid, covering convolution algebras, induced representations, amenable groupoids, r-discrete principal groupoids, and automorphism groups, kms states, and crossed products. chapter iii presents some examples, including approximately-finite groupoids and the groupoids o_n. the appendix discusses the dimension group of the gicar algebra. the book also includes references, a notation index, and a subject index. the work is protected by copyright, and reproduction requires permission from the publisher.