diff --git a/KEYS.md b/KEYS.md
new file mode 100644
index 0000000..db6e6ce
--- /dev/null
+++ b/KEYS.md
@@ -0,0 +1,60 @@
+# Format
+Programs in NXTools currently recognise the following keys (## represents a hexadecimal number between 00 and 1F):
+
+```
+; Key Sources
+master_key_##                    : Master key, used to derive other keys. (0x10 bytes)
+aes_kek_generation_source        : Used to derive other aes-keks. (0x10 bytes)
+aes_key_generation_source        : Used to derive other aes-keys. (0x10 bytes)
+package2_key_source              : Used with master_key_## to derive package2_key_##. (0x10 bytes)
+ticket_commonkey_source          : Used with master_key_## to derive ticket_commonkey_##. (0x10 bytes)
+nca_header_kek_source            : Used with master_key_00, aes_kek_generation_source and aes_key_generation_source to generate nca_header_kek.  (0x10 bytes)
+nca_header_key_source            : Used with nca_header_kek to generate nca_header_key.  (0x20 bytes)
+nca_body_keak_application_source : Used with master_key_##, aes_kek_generation_source and aes_key_generation_source to generate nca_body_keak_application_##. (0x10 bytes)
+nca_body_keak_ocean_source       : Used with master_key_##, aes_kek_generation_source and aes_key_generation_source to generate nca_body_keak_ocean_##. (0x10 bytes)
+nca_body_keak_system_source      : Used with master_key_##, aes_kek_generation_source and aes_key_generation_source to generate nca_body_keak_system_##. (0x10 bytes)
+
+; Package1 keys
+package1_key_##                  : AES128 Key (0x10 bytes)
+
+; Package2 Keys 
+package2_key_##                  : AES128 Key (0x10 bytes)
+package2_sign_key_modulus        : RSA2048 Modulus (0x100 bytes)
+package2_sign_key_private        : RSA2048 Private Exponent (0x100 bytes)
+
+; Ticket Keys
+ticket_commonkey_##              : AES128 Key (0x10 bytes)
+
+; NCA Keys
+nca_header_key                   : AES128-XTS Key (0x20 bytes)
+nca_header_sign_key_modulus      : RSA2048 Modulus (0x100 bytes)
+nca_header_sign_key_private      : RSA2048 Private Exponent (0x100 bytes)
+nca_body_keak_application_##     : AES128 Key (0x10 bytes)
+nca_body_keak_ocean_##           : AES128 Key (0x10 bytes)
+nca_body_keak_system_##          : AES128 Key (0x10 bytes)
+
+; XCI Keys
+xci_header_key                   : AES128 Key (0x10 bytes)
+xci_header_sign_key_modulus      : RSA2048 Modulus (0x100 bytes)
+xci_header_sign_key_private      : RSA2048 Private Exponent (0x100 bytes)
+
+; ACID Keys
+acid_sign_key_modulus            : RSA2048 Modulus (0x100 bytes)
+acid_sign_key_private            : RSA2048 Private Exponent (0x100 bytes)
+```
+
+# Compatibility with hactool keyset files
+NXTools keyset files share the same keyset file format as [hactool](https://github.com/SciresM/hactool/blob/master/KEYS.md), but names of keys may differ. For compatibility, hactool names for equivalent keys are accepted.
+```
+titlekey_source                  : hactool alias for ticket_commonkey_source
+header_key_source                : hactool alias for nca_header_key_source
+header_kek_source                : hactool alias for nca_header_kek_source
+key_area_key_application_source  : hactool alias for nca_body_keak_application_source
+key_area_key_ocean_source        : hactool alias for nca_body_keak_ocean_source
+key_area_key_system_source       : hactool alias for nca_body_keak_system_source 
+titlekek_##                      : hactool alias for ticket_commonkey_##
+header_key                       : hactool alias for nca_header_key
+key_area_key_application_##      : hactool alias for nca_body_keak_application_##
+key_area_key_ocean_##            : hactool alias for nca_body_keak_ocean_##
+key_area_key_system_##           : hactool alias for nca_body_keak_system_##
+```
\ No newline at end of file
diff --git a/README.md b/README.md
index b49fba9..5073385 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,28 @@
 # NXTools
-Tools for NX (Nintendo Switch).
 
-== Tools ==
-* ncatool - read/extract *.nca
-* nstool - read *.npdm, read/extract PartitionFS (PFS0|HFS0) blobs (including *.nsp), read *.xci
-* tiktool - read ticket fields.
+Tools & Libraries for NX (Nintendo Switch).
 
-== Issues ==
-* [ncatool] nca section extraction not implemented
-* [nstool] romfs support not implemented
+![License](https://img.shields.io/badge/license-MIT-blue.svg)
+
+# Tools
+
+* (nstool)[/programs/nstool] - read *.npdm, read/extract PartitionFS (PFS0|HFS0) blobs (including *.nsp), read *.xci
+* (ncatool)[/programs/ncatool] - read/extract *.nca
+* (tiktool)[/programs/tiktool] - read ticket fields.
+
+# Libraries
+
+* (libfnd)[/lib/libfnd]	- Foundation library.
+* (libcrypto)[/lib/libcrypto]	- Cryptographic functions (AES,SHA,RSA). Wrapper for [mbedTLS](https://github.com/ARMmbed/mbedtls)
+* (libes)[/lib/libes]		- Handling of (NS relevant) eShop file type processing. (eTickets, etc)
+* (libnx)[/lib/libnx]		- Handling of NS file types
+
+# External Keys
+
+Programs/libraries don't embed any keys that are copyright protected. However keys can be imported via a keyset file. 
+
+For programs that support it, the keyset file can either be provided via the command line (see program usage for details). Alternatively a keyset file located in _$HOME/.switch/prod.keys_ (or _$HOME/.switch/dev.keys_ for dev) will be imported automatically if one is not provided at the command line.
+
+Keyset files are ASCII text files containing one key per line, in the form "key_name = HEXADECIMALKEY". Case and whitespace do not matter, ';' character can be used to insert comments.
+
+See [KEYS.md](/KEYS.md) for more details.
\ No newline at end of file