Henry Strutz was an associate professor of languages at State University of New York in Alfred, New York, when he put this book together. The volume I have has a publication date of 1972 - this is, however, the kind of book that doesn't really go out of date. Language does change, but the basics of languages remain steady over several generations in general, and German is no exception. The basic core of the language remains constant, so this book holds up over time. Subsequent printings of this book may add a verb here and drop a verb there (given the title, it will always try to stay at 501 verbs), but the vast majority will remain the same. I studied German at university almost 25 years ago, and first purchased this book to go along with my studies. While German is fairly standard in the patterns of conjugations for most verbs, German like most languages has exceptions to many rules, including exceptions to some of the most frequently used verbs, such as the verb constructions for to be (English is the same, with this being one of the most difficult verb constructions for non-English speakers to learn). The verb sein (bin, bist, ist, sind, seid, sind) is one of the most important verbs; haben is another important verb, given its `helping verb' status (true also in English), as it occurs in constructions with other verbs.
There are 501 verbs here, one each to a page, arranged in alphabetical order. From achten (to pay attention to) to zwingen (to force, compel), most of the verbs found in eighty percent or more of regular conversation and general writing are to be found here. Each page is laid out in a logical order, with indicative forms (the most common and simple forms) on the left, and subjunctive forms (primary and secondary, as appropriate) on the right. It steps through the various verb tenses: present, past (imperfect, perfect, and pluperfect), future and future perfect. Rare is the verb that doesn't follow these patterns - some verbs, such as geschehen (to happen, to take place, to come to pass) have simplified patterns given the use in parts of speech (rare is the sentence in English or in German where someone would say, `I have come to pass...').
Strutz has an introduction of 45 pages (not numbered along with the verbs, but rather using Roman numerals, so that the 501 verbs can correspond to 501 text pages). This introduces a very basic grammar, a discussion of the verb tenses and their uses, different kinds of conjugations, and sets out a pattern page in English to aid users in following the German pages of verbs.
In discussing word order, Strutz quotes Mark Twain, who once said of the German language, `The German goes to bed with his subject and wakes up with his verb.' According to Strutz, Twain is once supposed to have refused to leave a play, despite its being dreadful, because he was waiting for the verb. Strutz injects humour into the serious aspect of language study such as he can (how much can one do with a simple listing of verbs?), particularly in the early pages with grammar discussion. He also addresses pronunciation issues, and looks at particular forms that are regionally different. Knowing his audience is largely academic/student readers, he draws examples from literature, philosophy (Nietzsche), and music.
Despite this good introduction, this book should not be confused with being a German grammar or language study. This introductory material is but the briefest of introductions, intended primarily as a refresher for those who have studied German before, or are studying German concurrently with using this text.
Strutz has several indexes. There is an English-to-German index of words represented in the text; there is a German-to-English index in the same pattern. Many `prefix verbs' are conjugated on the primary pages - words like ankommen (to arrive) and bekommen (to receive); however, there are others for which only the basic verb is conjugated - prefix formations are included in the index in parenthetical form. Finally, there is a brief index of verbs identified by infinitive form, given that some verbs change sufficiently in various conjugate forms to not be intuitively obvious for the beginner to understand which word it is.
I'm trying to recapture my reading German this year, so that I can do some theological research using various German texts in the coming academic year. I find this book invaluable - it is perhaps of more value when one is trying to write than when one is trying to read, but it is still very useful, so much so that the binding on my copy has cracked from use.