diff --git a/Manuals/Tcpi-ug/Commons.ent b/Manuals/Tcpi-ug/Commons.ent
new file mode 100755
index 0000000..f5bcdd1
--- /dev/null
+++ b/Manuals/Tcpi-ug/Commons.ent
@@ -0,0 +1,23 @@
+<!--  
+    $Id$
+    This file defines entities for words and phrases frequently used
+    inside The CentOS Project Infrastructure manual.  It is a way of
+    normalizing the use of concepts inside the documentation and make
+    their maintainance easier to realize.
+-->
+
+<!-- About The CentOS Project -->
+
+<!ENTITY C          "CentOS">
+<!ENTITY TC         "The &C;">
+<!ENTITY TCP        "<ulink type='http' url='http://www.centos.org'>&TC; Project</ulink>">
+<!ENTITY TCC        "&TC; Community">
+<!ENTITY TCD        "&TC; Distribution">
+<!ENTITY TCMIRRORS  "<ulink url='http://mirrors.centos.org/'>&TC; Mirrors</ulink>">
+<!ENTITY TCWIKI     "<ulink type='http' url='http://wiki.centos.org/'>&TC; Wiki</ulink>">
+
+<!-- About The CentOS Project Infrastructure -->
+
+<!ENTITY TCPI       "The CentOS Project Infrastructure">
+<!ENTITY TCAR       "<ulink url='https://projects.centos.org/svn/artwork'>The CentOS Artwork Repository</ulink>">
+<!ENTITY TCPIUG     "<citetitle>&TCPI; User's Guide</citetitle>">
diff --git a/Manuals/Tcpi-ug/Connectivity.docbook b/Manuals/Tcpi-ug/Connectivity.docbook
new file mode 100644
index 0000000..8beb345
--- /dev/null
+++ b/Manuals/Tcpi-ug/Connectivity.docbook
@@ -0,0 +1,7 @@
+<part id="connectivity">
+
+    <title>Connectivity</title>
+
+    &connectivity-dialup;
+
+</part>
diff --git a/Manuals/Tcpi-ug/Licenses.ent b/Manuals/Tcpi-ug/Licenses.ent
new file mode 100755
index 0000000..dd7f27a
--- /dev/null
+++ b/Manuals/Tcpi-ug/Licenses.ent
@@ -0,0 +1,2 @@
+<!ENTITY licenses       SYSTEM "Licenses.docbook">
+<!ENTITY licenses-gfdl  SYSTEM "Licenses/gfdl.docbook">
diff --git a/Manuals/Tcpi-ug/Preface.docbook b/Manuals/Tcpi-ug/Preface.docbook
new file mode 100755
index 0000000..42c8578
--- /dev/null
+++ b/Manuals/Tcpi-ug/Preface.docbook
@@ -0,0 +1,9 @@
+<preface id="preface">
+
+    <title>Preface</title>
+
+    &preface-overview;
+    &preface-docconvs;
+    &preface-feedback;
+
+</preface>
diff --git a/Manuals/Tcpi-ug/Preface.ent b/Manuals/Tcpi-ug/Preface.ent
new file mode 100755
index 0000000..263be1d
--- /dev/null
+++ b/Manuals/Tcpi-ug/Preface.ent
@@ -0,0 +1,4 @@
+<!ENTITY preface                SYSTEM "Preface.docbook">
+<!ENTITY preface-overview       SYSTEM "Preface/overview.docbook">
+<!ENTITY preface-docconvs       SYSTEM "Preface/docconvs.docbook">
+<!ENTITY preface-feedback       SYSTEM "Preface/feedback.docbook">
diff --git a/Manuals/Tcpi-ug/Services.ent b/Manuals/Tcpi-ug/Services.ent
new file mode 100644
index 0000000..b76c2c0
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services.ent
@@ -0,0 +1,13 @@
+<!ENTITY services                   SYSTEM "Services.docbook">
+<!ENTITY services-dns               SYSTEM "Services/Dns.docbook">
+<!ENTITY services-dns-overview      SYSTEM "Services/Dns/overview.docbook">
+<!ENTITY services-mail              SYSTEM "Services/Mail.docbook">
+<!ENTITY services-mail-overview     SYSTEM "Services/Mail/overview.docbook">
+<!ENTITY services-mail-mta          SYSTEM "Services/Mail/mta.docbook">
+<!ENTITY services-mail-mda          SYSTEM "Services/Mail/mda.docbook">
+<!ENTITY services-mail-saslauthd    SYSTEM "Services/Mail/saslauthd.docbook">
+<!ENTITY services-mail-mua          SYSTEM "Services/Mail/mua.docbook">
+<!ENTITY services-http              SYSTEM "Services/Http.docbook">
+<!ENTITY services-http-overview     SYSTEM "Services/Http/overview.docbook">
+<!ENTITY services-ldap              SYSTEM "Services/Ldap.docbook">
+<!ENTITY services-ldap-overview     SYSTEM "Services/Ldap/overview.docbook">
diff --git a/Manuals/Tcpi-ug/Services/Dns.docbook b/Manuals/Tcpi-ug/Services/Dns.docbook
new file mode 100644
index 0000000..78dd877
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Dns.docbook
@@ -0,0 +1,11 @@
+<chapter id="services-dns">
+
+    <title>Domain Name Service</title>
+
+    <para>
+        ...
+    </para>
+
+    &services-dns-overview;
+
+</chapter>
diff --git a/Manuals/Tcpi-ug/Services/Dns/overview.docbook b/Manuals/Tcpi-ug/Services/Dns/overview.docbook
new file mode 100644
index 0000000..2f57c37
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Dns/overview.docbook
@@ -0,0 +1,9 @@
+<sect1 id="services-dns-overview">
+
+    <title>Overview</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Http.docbook b/Manuals/Tcpi-ug/Services/Http.docbook
new file mode 100644
index 0000000..ce85a8b
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Http.docbook
@@ -0,0 +1,11 @@
+<chapter id="services-http">
+
+    <title>Web Service</title>
+
+    <para>
+        ...
+    </para>
+
+    &services-http-overview;
+
+</chapter>
diff --git a/Manuals/Tcpi-ug/Services/Http/overview.docbook b/Manuals/Tcpi-ug/Services/Http/overview.docbook
new file mode 100644
index 0000000..00335b6
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Http/overview.docbook
@@ -0,0 +1,9 @@
+<sect1 id="services-http-overview">
+
+    <title>Overview</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Ldap.docbook b/Manuals/Tcpi-ug/Services/Ldap.docbook
new file mode 100644
index 0000000..eba7579
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Ldap.docbook
@@ -0,0 +1,11 @@
+<chapter id="services-ldap">
+
+    <title>Directory Service</title>
+
+    <para>
+        ...
+    </para>
+
+    &services-ldap-overview;
+
+</chapter>
diff --git a/Manuals/Tcpi-ug/Services/Ldap/overview.docbook b/Manuals/Tcpi-ug/Services/Ldap/overview.docbook
new file mode 100644
index 0000000..f2af74e
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Ldap/overview.docbook
@@ -0,0 +1,9 @@
+<sect1 id="services-ldap-overview">
+
+    <title>Overview</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Mail.docbook b/Manuals/Tcpi-ug/Services/Mail.docbook
new file mode 100644
index 0000000..04a47d2
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Mail.docbook
@@ -0,0 +1,10 @@
+<chapter id="services-mail">
+
+    <title>Mail Service</title>
+
+    &services-mail-overview;
+    &services-mail-mta;
+    &services-mail-mda;
+    &services-mail-mua;
+
+</chapter>
diff --git a/Manuals/Tcpi-ug/Services/Mail/mda.docbook b/Manuals/Tcpi-ug/Services/Mail/mda.docbook
new file mode 100644
index 0000000..4b8971f
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Mail/mda.docbook
@@ -0,0 +1,9 @@
+<sect1 id="service-mail-mda">
+
+    <title>Mail Delivery Agent</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Mail/mta.docbook b/Manuals/Tcpi-ug/Services/Mail/mta.docbook
new file mode 100644
index 0000000..eeabea3
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Mail/mta.docbook
@@ -0,0 +1,9 @@
+<sect1 id="service-mail-mta">
+
+    <title>Mail Transfer Agent</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Mail/mua.docbook b/Manuals/Tcpi-ug/Services/Mail/mua.docbook
new file mode 100644
index 0000000..319d167
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Mail/mua.docbook
@@ -0,0 +1,9 @@
+<sect1 id="service-mail-mua">
+
+    <title>Mail User Agent</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Mail/overview.docbook b/Manuals/Tcpi-ug/Services/Mail/overview.docbook
new file mode 100644
index 0000000..b9693a6
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Mail/overview.docbook
@@ -0,0 +1,58 @@
+<sect1 id="services-mail-overview">
+
+    <title>Overview</title>
+
+    <para>
+        The mail service provides the software required to let you
+        send/receive mail messages to/from others. The mail service is
+        supported by three basic components: the Mail Transfer Agent
+        (MTA), the Mail Delivery Agent (MDA) and the Mail User Agent
+        (MUA). The MTA is the program your mail client sends mail
+        messages to. The MDA, on the other hand, is the program your
+        mail client reads mail message from (i.e., this is the program
+        that lets you access your mailbox).  The saslauthd daemon is
+        used by the MDA to authenticate user's credentials (e.g., the
+        information required to grant access to an specific mailbox)
+        and in some cases by the MTA to authenticate users before
+        sending mail to it.  The MTA will listen on all network
+        interfaces it is attached to and will receive mail sent to
+        specific users inside specific domain names.
+    </para>
+
+    <para>
+        Inside &TCD; there is support for different MTAs (e.g.,
+        Sendmail, Postfix and Exim).  By default, the
+        <application>Sendmail</application> program is used as mail
+        transfer agent, however, we want to use Postfix for our
+        configuration. This way, to use Postfix as default mail
+        transfer agent and not Sendmail, it is required to use the
+        <command>alternatives</command> command.  This command will
+        present you a menu to chose between available mail transfer
+        agents installed in the system, so you can choose Posfix as
+        default option. Now that you've made Postfix the default mail
+        transfer agent, you can saftly remove the sendmail package to
+        avoid unused software to remain inside the computer.
+    </para>
+
+    <para>
+        Inside &TCD; there is support for different MDA (e.g., Cyrus
+        IMPA and Dovecot). By default, the Dovecot program is used as
+        mail delivery agent (which doesn't require any intermediate
+        daemon for athentication), however, we want to use Cyrus IMAP
+        for our configuration (which does require an intermediate
+        daemon called saslauthd for authentication).
+    </para>
+
+    <para>
+        Inside &TCD; there is support for different MUA (e.g.,
+        Evolution, Thunderbird and Mutt). By default, the Evolution
+        program is used and we stay with it :).
+    </para>
+
+    <para>
+        In this chapter we describe how to configure each one of these
+        components to let you send/receive e-mails to/from your
+        friends.
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/Services/Mail/saslauthd.docbook b/Manuals/Tcpi-ug/Services/Mail/saslauthd.docbook
new file mode 100644
index 0000000..4211a1b
--- /dev/null
+++ b/Manuals/Tcpi-ug/Services/Mail/saslauthd.docbook
@@ -0,0 +1,9 @@
+<sect1 id="service-mail-saslauthd">
+
+    <title>Sasl Authentication Server</title>
+
+    <para>
+        ...
+    </para>
+
+</sect1>
diff --git a/Manuals/Tcpi-ug/tcpi-ug.docbook b/Manuals/Tcpi-ug/tcpi-ug.docbook
new file mode 100755
index 0000000..a677227
--- /dev/null
+++ b/Manuals/Tcpi-ug/tcpi-ug.docbook
@@ -0,0 +1,80 @@
+<?xml version="1.0"?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
+               "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd"
+               [
+
+<!ENTITY % Commons.ent          SYSTEM "Commons.ent">
+<!ENTITY % Preface.ent          SYSTEM "Preface.ent">
+<!ENTITY % Connectivity.ent     SYSTEM "Connectivity.ent">
+<!ENTITY % Services.ent         SYSTEM "Services.ent">
+<!ENTITY % Licenses.ent         SYSTEM "Licenses.ent">
+
+%Commons.ent;
+%Preface.ent;
+%Connectivity.ent;
+%Services.ent;
+%Licenses.ent;
+]>
+
+<book lang="en_US">
+
+    <!-- Front matter -->
+    <title>The CentOS Project Infrastructure</title>
+    <subtitle>User's Guide</subtitle>
+
+    <bookinfo>
+        <author>
+            <firstname>Alain</firstname>
+            <surname>Reguera Delgado</surname>
+        </author>
+
+        <!-- Copyright: The copyright page is verso and contains the
+        copyright notice, the publishing/printing history, the country
+        where printed, ISBN and/or CIP information.  The page is
+        usually typeset in a smaller font than the normal text. -->
+        <copyright>
+            <year>2011</year>
+            <holder>&TCP;. All rights reserved.</holder>
+        </copyright>
+
+        <legalnotice>
+            <para>
+              Permission is granted to copy, distribute and/or modify
+              this document under the terms of the GNU Free
+              Documentation License, Version 1.2 or any later version
+              published by the Free Software Foundation; with no
+              Invariant Sections, no Front-Cover Texts, and no
+              Back-Cover Texts. A copy of the license is included in
+              <xref linkend="licenses-gfdl" />.
+            </para>
+        </legalnotice>
+
+        <revhistory>
+            <revision> 
+            <revnumber>1.0</revnumber>
+            <date>Today</date>
+            <author>
+                <firstname>Alain</firstname>
+                <surname>Reguera Delgado</surname>
+            </author>
+            <revdescription>
+            <para>
+                Under development.
+            </para>
+            </revdescription>
+            </revision> 
+        </revhistory>
+
+    </bookinfo>
+
+    <!-- Front matter -->
+    &preface;
+
+    <!-- Main matter -->
+    &connectivity;
+    &services;
+
+    <!-- Back matter -->
+    &licenses;
+
+</book>