Knowing the date of first publication of each title in the Inspector Lynley series helps with reading the books in chronological order. On the website of the author of the series, there is a complete list of the books with a publication date stated for each book.
The first book in this series of 19 novels is "A Great Deliverance," with a publication date of 1988, while the last novel as of 2015 is "A Banquet of Consequences," published in 2015.
The series of the mystery novels about inspector Lynley is the work of Elizabeth George. As of 2015, she is also the author of seven books that do not belong in the series.