I have long considered Francis Schaeffer to be one of the most influential people on my thinking. His three volume set: The God Who is There, He Is There and He is Not Silent, and Escape From Reason as well as his short volume The Mark of the Christian have been beneficial reads. I decided that this summer, I would try to read through his complete works--22 books, 5 volumes, 2262 pages.
Once again, I really appreciated his three apologetics books. His work is essential for any serious student of understanding Christian worldview and how Christianity applies to all of life. Schaeffer's knowledge of a wide variety of fields: philosophy, art, music, culture, and religion come together well in these books.
Beyond these books, I really appreciated Genesis in Space and Time in which Schaeffer defended the truthfulness of Genesis 1-11. He makes a strong call for understanding these early chapters of the Bible. True Spirituality is also a must read, perhaps one of the finest of his books. In this book, he defends the orthodox Christian position. His books Death in the City and The Great Evangelical Disaster further support the need for holding to an orthodox position and standing for True Truth. Finally, his book Whatever Happened to the Human Race, which he co-authored with C Everett Koop was an excellent defense of the uniqueness and value of man.
There was a lot of repetition of ideas from book to book which others have raised as a criticism, but I don't necessarily think it is a bad thing. It was a beneficial thing to see his ideas re-presented on multiple occasions. Schaeffer was uniquely gifted as a cultural critic, philosopher and prophet. His words, written 30 to 40 years ago in most cases show a direct application to today's society. His balance of truth and love is nearly unparalleled.