diff --git a/src/events/intro/introSummary.tw b/src/events/intro/introSummary.tw
index c3cbeeabfb1328f3de02496c1cee012294848742..c3d4e88c8ce23f9127a7722bc3227a6fe11a7a26 100644
--- a/src/events/intro/introSummary.tw
+++ b/src/events/intro/introSummary.tw
@@ -867,6 +867,17 @@ Image display
 <br>
 // This mod alters how prosthetics system works and adds some content.//
 
+<<if $secExp == 1>>
+	The Security Expansion Mod is ''enabled.''
+[[Disable|Intro Summary][$secExp = 0]]
+<<else>>
+	The Security Expansion Mod is ''disabled.''
+[[Enable|Intro Summary][$secExp = 1]]
+<</if>>
+<br>
+// This mod introduces security and crime in the arcology, as well as attacks and battles.//
+
+
 <br><br>
 <<link "Continue">>
 	<<if $freshPC == 1 || $saveImported == 0>>
diff --git a/src/events/intro/pcExperienceIntro.tw b/src/events/intro/pcExperienceIntro.tw
index 2f2cca0b51d5c2d4a603fe3b51b990feb2d99369..e06fa2169c532069431fc5f694ba3da35f2a0250 100644
--- a/src/events/intro/pcExperienceIntro.tw
+++ b/src/events/intro/pcExperienceIntro.tw
@@ -8,13 +8,13 @@ You're a relative unknown in the Free Cities, but it's clear you're already acco
 <br>
 
 <br>[[Idle wealth|PC Rumor Intro][$PC.career = "wealth"]]
-<br>&nbsp;&nbsp;&nbsp;&nbsp;//Start with extra money, but you will find harder to maintain authority. Your starting slaves will have two free levels of sex skills available.//
+<br>&nbsp;&nbsp;&nbsp;&nbsp;//Start with extra money<<if $showSecExp == 1>>, but you will find harder to maintain authority<</if>>. Your starting slaves will have two free levels of sex skills available.//
 <br>[[Venture capitalism|PC Rumor Intro][$PC.career = "capitalist"]]
 <br>&nbsp;&nbsp;&nbsp;&nbsp;//You will be more effective at business pursuits. Your starting slaves will have a free level of prostitution skill available.//
 <br>[[Private military work|PC Rumor Intro][$PC.career = "mercenary"]]
-<br>&nbsp;&nbsp;&nbsp;&nbsp;//You retain mercenary contacts and your security skills will make it easier to keep the arcology safe. Your starting slaves will have free trust available.//
+<br>&nbsp;&nbsp;&nbsp;&nbsp;//You retain mercenary contacts<<if $showSecExp == 1>> and your security skills will make it easier to keep the arcology safe<<else>> and security skills<</if>>. Your starting slaves will have free trust available.//
 <br>[[Slaving|PC Rumor Intro][$PC.career = "slaver"]]
-<br>&nbsp;&nbsp;&nbsp;&nbsp;//Your slave breaking experience will be useful and authority will be easier to maintain. Your starting slaves will have free devotion available.//
+<br>&nbsp;&nbsp;&nbsp;&nbsp;//Your slave breaking experience will be useful<<if $showSecExp == 1>> and authority will be easier to maintain<</if>>. Your starting slaves will have free devotion available.//
 <br>[[Arcology engineering|PC Rumor Intro][$PC.career = "engineer"]]
 <br>&nbsp;&nbsp;&nbsp;&nbsp;//Upgrading the arcology will be cheaper. Also, the arcology will start with basic economic upgrades already installed.//
 <br>[[Slave surgery|PC Rumor Intro][$PC.career = "medicine"]]
@@ -22,10 +22,24 @@ You're a relative unknown in the Free Cities, but it's clear you're already acco
 <br>[[Minor celebrity|PC Rumor Intro][$PC.career = "celebrity"]]
 <br>&nbsp;&nbsp;&nbsp;&nbsp;//Start with extra reputation. Your starting slaves will have a free level of entertainment skill available.//
 <br>[[High class escort|PC Rumor Intro][$PC.career = "escort"]]
-<br>&nbsp;&nbsp;&nbsp;&nbsp;//As an ex-whore, you will find it hard to maintain reputation and authority. Your starting slaves will have a free level of sex skills available, along with a free level of entertainment and prostitution.//
+<br>&nbsp;&nbsp;&nbsp;&nbsp;//As an ex-whore, you will find it hard to maintain reputation<<if $showSecExp == 1>> and authority<</if>>. Your starting slaves will have a free level of sex skills available, along with a free level of entertainment and prostitution.//
 <br>[[Servant|PC Rumor Intro][$PC.career = "servant"]]
-<br>&nbsp;&nbsp;&nbsp;&nbsp;//As an ex-servant, you will find it hard to maintain reputation and authority. You know how to lower your upkeep, but not conduct business. Your starting slaves will have free trust and devotion.//
+<br>&nbsp;&nbsp;&nbsp;&nbsp;//As an ex-servant, you will find it hard to maintain reputation<<if $showSecExp == 1>> and authority<</if>>. You know how to lower your upkeep, but not conduct business. Your starting slaves will have free trust and devotion.//
 <br>[[Gang Leader|PC Rumor Intro][$PC.career = "gang"]]
-<br>&nbsp;&nbsp;&nbsp;&nbsp;//As a gang leader, you know how to haggle slaves and assert your authority, but you will find reputation quite hard to maintain. Your starting slaves will be fitter and posses a free level of combat skill.//
+<br>&nbsp;&nbsp;&nbsp;&nbsp;//As a gang leader, you know how to haggle slaves<<if $showSecExp == 1>> and assert your authority<</if>>, but you will find reputation quite hard to maintain. Your starting slaves will be fitter and posses a free level of combat skill.//
 
 <</if>>
+
+<br><br>
+
+<<if $showSecExp == 0>>
+	<<link "Show Security Expansion changes">>
+		<<set $showSecExp = 1>>
+		<<goto "terrainIntro">>
+	<</link>>
+<<else>>
+	<<link "Hide Security Expansion changes">>
+		<<set $showSecExp = 0>>
+		<<goto "terrainIntro">>
+	<</link>>
+<</if>>
\ No newline at end of file
diff --git a/src/events/intro/terrainIntro.tw b/src/events/intro/terrainIntro.tw
index 07450df7e30fdc7eef1a6f2d68d91e9e61dcf4ff..c5f48ceccecf078495807ebf5d2822a88750940c 100644
--- a/src/events/intro/terrainIntro.tw
+++ b/src/events/intro/terrainIntro.tw
@@ -59,6 +59,23 @@ Finally, a few Free Cities have been carved out from old world cities. Urban dec
 <br>&nbsp;&nbsp;&nbsp;&nbsp;Moderate ease of commerce with the old world.
 <br>&nbsp;&nbsp;&nbsp;&nbsp;@@.red;Very low@@ access to refugees and other desperate people.
 <br>&nbsp;&nbsp;&nbsp;&nbsp;@@.green;Very high@@ cultural independence.
-<br>&nbsp;&nbsp;&nbsp;&nbsp;Ensures access to slaves from all over the world and will not associate the arcology with a continent. <br>Oceanic arcologies will not be subjects of attacks.
+<br>&nbsp;&nbsp;&nbsp;&nbsp;Ensures access to slaves from all over the world and will not associate the arcology with a continent.
+<<if $showSecExp == 1>>
+<br>Oceanic arcologies will not be subjects of attacks.
+<</if>>
 
 <</if>>
+
+<br><br>
+
+<<if $showSecExp == 0>>
+	<<link "Show Security Expansion changes">>
+		<<set $showSecExp = 1>>
+		<<goto "terrainIntro">>
+	<</link>>
+<<else>>
+	<<link "Hide Security Expansion changes">>
+		<<set $showSecExp = 0>>
+		<<goto "terrainIntro">>
+	<</link>>
+<</if>>
\ No newline at end of file
diff --git a/src/uncategorized/BackwardsCompatibility.tw b/src/uncategorized/BackwardsCompatibility.tw
index 762741ea738c4f88e4d0ccee76df3baf10ad6ce6..1ecb2dbd0256c65bb7be78d0a7a5319e9e1915a8 100644
--- a/src/uncategorized/BackwardsCompatibility.tw
+++ b/src/uncategorized/BackwardsCompatibility.tw
@@ -611,7 +611,9 @@
 <</if>>
 
 /* Sec Exp */
+<<if $secExp == 1>>
 <<include "SecExpBackwardCompatibility">>
+<</if>>
 
 <<if ndef $arcologies[0].FSAztecRevivalist>>
 	<<for _bci = 0; _bci < $arcologies.length; _bci++>>
diff --git a/src/uncategorized/arcmgmt.tw b/src/uncategorized/arcmgmt.tw
index 3d8c3bd5d18499701c0486e6d124f31e4442ada5..528251733919eaa356a46877e31fad3b70a48338 100644
--- a/src/uncategorized/arcmgmt.tw
+++ b/src/uncategorized/arcmgmt.tw
@@ -506,6 +506,7 @@ earning you @@.yellowgreen;¤_earnings.@@
 		Growth was subsidized as planned.
 		<<set _AWeekGrowth++>>
 	<</if>>
+	<<if $secExp == 1>>
 	<<if $authority > 18000>>
 		Your authority is so high it discourages new business, slowing down the economic growth of the arcology.
 		<<set _AWeekGrowth-->>
@@ -517,6 +518,7 @@ earning you @@.yellowgreen;¤_earnings.@@
 		Your arcology low security is an instability factor simply too dangerous to be ignored. Many businesses avoid your arcology because of this.
 		<<set _AWeekGrowth-->>
 	<</if>>
+	<</if>>
 	<<if $controlLeaks == 1>>
 		The authenticity department prepares extremely accurate, but false financial reports, misleading many of your competitors, allowing your arcology more space to grow undisturbed.
 		<<set _AWeekGrowth++>>
diff --git a/src/uncategorized/economics.tw b/src/uncategorized/economics.tw
index 903125d457e1022ac970d07796361715e1ac847f..81c80254dd61e69202fd94d3d866a54baa1e5899 100644
--- a/src/uncategorized/economics.tw
+++ b/src/uncategorized/economics.tw
@@ -54,8 +54,9 @@
 <</if>>
 
 <br><br>
-
+<<if $secExp == 1>>
 <<include "securityReport">>
+<</if>>
 
 <<else>>
 <<CreateSimpleTabs>>
@@ -67,7 +68,11 @@
 	<<if $corpAnnounced == 1>>
 	<button class="tablinks" onclick="opentab(event, 'Corporation')">Corporation</button>
 	<</if>>
+	<<if $secExp == 1>>
 	<button class="tablinks" onclick="opentab(event, 'Reputation')">Reputation and Authority</button>
+	<<else>>
+	<button class="tablinks" onclick="opentab(event, 'Reputation')">Reputation</button>
+	<</if>>
 	<button class="tablinks" onclick="opentab(event, 'Management')">Arcology Management</button>
 	<<if ($PC.boobs == 1 && $PC.boobsBonus > 0) || $PC.pregKnown == 1 || $playerAging != 0>>
 	<button class="tablinks" onclick="opentab(event, 'Personal')">Personal Notes</button>
@@ -75,7 +80,9 @@
 	<<if $FSAnnounced > 0>>
 	<button class="tablinks" onclick="opentab(event, 'Societies')">Society Development</button>
 	<</if>>
-	<button class="tablinks" onclick="opentab(event, 'securityReport')">Security Report</button>
+	<<if $secExp == 1>>
+	<button class="tablinks" onclick="opentab(event, 'securityReport')">Security</button>
+	<</if>>
 </div>
 
 <div id="Arcologies" class="tabcontent">
diff --git a/src/uncategorized/options.tw b/src/uncategorized/options.tw
index 2d1b5c9f599092a54f5b94601a42cec8aa1b1bc0..e1dac91ac8cf6849f0c38b6bf733aa921e297780 100644
--- a/src/uncategorized/options.tw
+++ b/src/uncategorized/options.tw
@@ -7,6 +7,7 @@
 This save was created using FC version $ver build $releaseID.
 <br>
 &nbsp;&nbsp;&nbsp;&nbsp;[[Apply Backwards Compatibility Update|Backwards Compatibility]]
+&nbsp;&nbsp;&nbsp;&nbsp;[[Apply Backwards Compatibility Update only for Security Expansion mod|SecExpBackwardCompatibility]]
 
 <br>
 <<if ($autosave == 0)>>
@@ -346,6 +347,17 @@ Curative side effects are @@.red;DISABLED@@. [[Enable|Options][$curativeSideEffe
 	Cybernetics Mod is currently @@.cyan;ENABLED@@. [[Disable|Options][$cyberMod = 0]]
 <</if>>
 
+<<if $secExp == 0>>
+	The Security Expansion mod is @@.red;disabled@@.
+	<<link "Enable">>
+		<<set $secExp = 1>>
+		<<include "SecExpBackwardCompatibility">>
+	<</link>>
+<<else>>
+	The Security Expansion Mod is currently @@.cyan;ENABLED@@. [[Disable|Options][$SFMODToggle = 0]]
+<</if>> 
+//The mod can be activated in any moment, but it may result in unbalanced gameplay if activated very late//
+
 <br><br>
 ''CHEATING/DEV OPTIONS''
 <br>
diff --git a/src/uncategorized/reputation.tw b/src/uncategorized/reputation.tw
index 97bd492c74f9325dee17a9d8cd29de834b373e54..d6d75454cd6dd848ca819099d6459525d85dc92d 100644
--- a/src/uncategorized/reputation.tw
+++ b/src/uncategorized/reputation.tw
@@ -670,5 +670,6 @@ On formal occasions, you are announced as $PCTitle.
 <</if>>
 
 <br><br>
-
-<<include "authorityReport">>
\ No newline at end of file
+<</if $secExp == 1>>
+<<include "authorityReport">>
+<</if>>
\ No newline at end of file
diff --git a/src/uncategorized/scheduledEvent.tw b/src/uncategorized/scheduledEvent.tw
index 0459c3f0c7f10753434c6a6548b1f27ef3e73b97..938152fc3a7bae3c8c60e7c9aa90b4096beeb9c4 100644
--- a/src/uncategorized/scheduledEvent.tw
+++ b/src/uncategorized/scheduledEvent.tw
@@ -89,9 +89,9 @@
 <<elseif $week == 90>>
 	<<set $fcnn = ["FCNN service has been temporarily suspended. Please stand by."]>>
 <</if>>
-
+<<if $secExp == 1>>
 <<include "attackGenerator">>
-
+<</if>>
 <<if $rivalOwner == -1>>
 	<<goto "P rival initiation">>
 <<elseif $attackThisWeek == 1>>
diff --git a/src/uncategorized/storyCaption.tw b/src/uncategorized/storyCaption.tw
index 9b84bd8dad16f975ababa97ae7991d945bbb3dfb..81157b435a3e0f9669ede27addb2b1ddd692edde 100644
--- a/src/uncategorized/storyCaption.tw
+++ b/src/uncategorized/storyCaption.tw
@@ -196,6 +196,7 @@
 <</if>>
 ($rep)
 </span>
+<<if $secExp == 1>>
 <br>@@.darkviolet;Auth@@ |
 <<set $authority = Math.clamp(Math.trunc($authority), 0, 20000)>>
 <span id="auth">
@@ -244,6 +245,7 @@
 </span>
 <br>@@.deepskyblue;Security@@ | @@.deepskyblue;<<print Math.trunc($security)>>%@@
 <br>@@.orangered;Crime@@ | @@.orangered;<<print Math.trunc($crime)>>%@@
+<</if>>
 <<if (_Pass == "Main")>>
 	<<if ($cheatMode) && ($cheatModeM)>>
 	<<set _TRep = $rep>>
@@ -428,7 +430,9 @@
 		<</if>>
 		<br><span id="PAOButton"><<link [[Personal Assistant|Personal assistant options]]>><</link>></span> @@.cyan;[T]@@
 		<br><span id="policyButton"><<link [[Policies]]>><</link>></span> @@.cyan;[Y]@@
+		<<if $secExp == 1>>
 		<br><<link [[Edicts|edicts]]>><</link>>
+		<</if>>
 		<<if $FSAnnounced>>
 			<br><span id="FSButton"><<link [[Future Societies|Future Society]]>><</link>></span> @@.cyan;[F]@@
 		<</if>>
@@ -441,6 +445,7 @@
 	<br><br>
 	<br><span id="managePenthouse"><<link "Manage Penthouse">><<set $nextButton = "Back", $nextLink = _Pass>><<goto "Manage Penthouse">><</link>></span> @@.cyan;[P]@@
 	<br><span id="managePerson"><<link "Manage Personal Affairs">><<set $nextButton = "Back", $nextLink = _Pass>><<goto "Manage Personal Affairs">><</link>></span> @@.cyan;[X]@@
+	<<if $secExp == 1>>
 	<<if $propHub == 1>>
 		<br><<link "Manage Propaganda">><<set $nextButton = "Back", $nextLink = _Pass>><<goto "propagandaHub">><</link>>
 	<</if>>
@@ -450,6 +455,7 @@
 	<<if $secBarracks == 1>>
 		<br><<link "Manage Military">><<set $nextButton = "Back", $nextLink = _Pass>><<goto "secBarracks">><</link>>
 	<</if>>
+	<</if>>
 	<<if $cyberMod != 0 && $researchLab.built == "true">>
 		<br>[[Manage Research Lab|Research Lab][$temp = 0]]
 	<</if>>
@@ -458,7 +464,9 @@
 	<</if>>
 	<br><span id="PAOButton"><<link [[Personal Assistant|Personal assistant options]]>><</link>></span> @@.cyan;[T]@@
 	<br><span id="policyButton"><<link [[Policies]]>><</link>></span> @@.cyan;[Y]@@
+	<<if $secEx == 1>>
 	<br><<link [[Edicts|edicts]]>><</link>>
+	<</if>>
 	<<if $FSAnnounced>>
 		<br><span id="FSButton"><<link [[Future Societies|Future Society]]>><</link>></span> @@.cyan;[F]@@
 	<</if>>