Thank you very much to my modest contribution to the world of global open source information! I really appreciate you visiting, feel free to browse and do not hesitate to contact me if you have any additions!

As an OSINT-ian, I am a source-horse. Starting at the library academy in the early eighties with a modest list of important open sources to learn to know and how to use, I started with typing that list in my word-processor. It grew and grew, adding more and more interesting sources. And the list moved, from paper, to a floppy-disk, then to a diskette, then online into a modest database to what it is today

The Repertorium is a collection of important or useful open sources on the World Wide Web, sometime on other parts of the Internet. The Repertorium is used today as my first entry point to important search engines and other sources relevant to OSINT especially those interested in international news, international relations, conflict, and intelligence. Note that there are also links to international libraries, catalogues and off course commercial information providers.

There are basically four parts:

1. The first block are about 10 categories of search engines. Some have links to their help-pages. Search engines include directories, single search engines, meta search engines, citation indexes, deep web search engines (?) and more.
2. The second block are Premium providers. Sources that more or less are validated or have something of quality control. This category includes libraries, bibliographies, catalogues, commercial information providers (vendors) etc.
3. The third block is Reference, websites used to build on your information profile before starting your research. Dictionaries, encyclopedias, general reference and terminology are listed here.
4. The last block are all the subjects, in alphabetical order.

Sources are selected based on their relevance for the broad general subject of international relations, conflict, news and politics. Sources should have some authority and a clear author, publisher or any impressum. Sources should be detailed enough to allow proper validation. For each category, only the most important sources are selected.

Please note: the global information landscape of open sources consist of very much more than just the world wide web. Do not forget print sources, human sources, libraries, radio/TV etc.!

The company is involved in delivering professional Open Source Intelligence training programmes and workshops to an international group of customers, mainly government and private sector as well as international missions.

I have a 20+ year background at the Dutch Defence Intelligence & Security Service. I was hired in 1990 to establish, design and run an Open Source Intelligence production capability. In that time, nobody knew what OSINT was and I was probably the first in Europe ever to start with OSINT.

In addition, Internet did exist, but hardly anyone had access and their was no such thing as World Wide Web, nor Microsoft Windows.

In the years as Head bureau of OSINT for the service, I gradually developed a thorough, robust and durable methodology to do OSINT research. The method became known as Arno's OSINT Methodology and is the core subject of all my training and consultancy.

I resigned my job at the service in 2013 to devote myself fully to my company, sharing my vast knowledge on OSINT methods & techniques in the form of training programmes, short courses and extensive consultancy to an international group of clients.

The Repertorium comes with absolutely no garantuee whatsoever. It's use is entirely at your own risk. I do not accept any responsibility of the (mis)use of the information contained in the Repertorium.

The Repertorium comes free of charge.

The Repertorium is free of charge to use for all colleagues. There is no need to login with credentials, thus users will not leave behind sensitive data. Therefore, just in this case I do not make use of HTTPS but of simple HTTP.

I do not record in any way your private data, your IP address or other data that you may share when using the Repertorium. I also do not store cookies on your machines.

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