diff --git a/Library/Homebrew/cask/installer.rb b/Library/Homebrew/cask/installer.rb
index b7d4309ca9..123796b456 100644
--- a/Library/Homebrew/cask/installer.rb
+++ b/Library/Homebrew/cask/installer.rb
@@ -574,15 +574,7 @@ on_request: true)
 
     sig { void }
     def forbidden_tap_check
-      forbidden_taps = Homebrew::EnvConfig.forbidden_taps
-      return if forbidden_taps.blank?
-
-      forbidden_taps_set = Set.new(forbidden_taps.split.filter_map do |tap|
-        Tap.fetch(tap)
-      rescue Tap::InvalidNameError
-        opoo "Invalid tap name in `HOMEBREW_FORBIDDEN_TAPS`: #{tap}"
-        nil
-      end)
+      return if Tap.allowed_taps.blank? && Tap.forbidden_taps.blank?
 
       owner = Homebrew::EnvConfig.forbidden_owner
       owner_contact = if (contact = Homebrew::EnvConfig.forbidden_owner_contact.presence)
@@ -592,27 +584,31 @@ on_request: true)
       unless skip_cask_deps?
         cask_and_formula_dependencies.each do |cask_or_formula|
           dep_tap = cask_or_formula.tap
-          next if dep_tap.blank?
-          next unless forbidden_taps_set.include?(dep_tap)
+          next if dep_tap.blank? || (dep_tap.allowed_by_env? && !dep_tap.forbidden_by_env?)
 
           dep_full_name = cask_or_formula.full_name
-          raise CaskCannotBeInstalledError.new(@cask, <<~EOS
-            The installation of #{@cask} has a dependency #{dep_full_name}
-            but the #{dep_tap} tap was forbidden by #{owner} in `HOMEBREW_FORBIDDEN_TAPS`.#{owner_contact}
-          EOS
-          )
+          error_message = +"The installation of #{@cask} has a dependency #{dep_full_name}\n" \
+                           "from the #{dep_tap} tap but #{owner} "
+          error_message << "has not allowed this tap in `HOMEBREW_ALLOWED_TAPS`" unless dep_tap.allowed_by_env?
+          error_message << " and\n" if !dep_tap.allowed_by_env? && dep_tap.forbidden_by_env?
+          error_message << "has forbidden this tap in `HOMEBREW_FORBIDDEN_TAPS`" if dep_tap.forbidden_by_env?
+          error_message << ".#{owner_contact}"
+
+          raise CaskCannotBeInstalledError.new(@cask, error_message)
         end
       end
 
       cask_tap = @cask.tap
-      return if cask_tap.blank?
-      return unless forbidden_taps_set.include?(cask_tap)
+      return if cask_tap.blank? || (cask_tap.allowed_by_env? && !cask_tap.forbidden_by_env?)
 
-      raise CaskCannotBeInstalledError.new(@cask, <<~EOS
-        The installation of #{@cask.full_name} has the tap #{cask_tap}
-        which was forbidden by #{owner} in `HOMEBREW_FORBIDDEN_TAPS`.#{owner_contact}
-      EOS
-      )
+      error_message = +"The installation of #{@cask.full_name} has the tap #{cask_tap}\n" \
+                       "but #{owner} "
+      error_message << "has not allowed this tap in `HOMEBREW_ALLOWED_TAPS`" unless cask_tap.allowed_by_env?
+      error_message << " and\n" if !cask_tap.allowed_by_env? && cask_tap.forbidden_by_env?
+      error_message << "has forbidden this tap in `HOMEBREW_FORBIDDEN_TAPS`" if cask_tap.forbidden_by_env?
+      error_message << ".#{owner_contact}"
+
+      raise CaskCannotBeInstalledError.new(@cask, error_message)
     end
 
     sig { void }
diff --git a/Library/Homebrew/env_config.rb b/Library/Homebrew/env_config.rb
index ef9b72ea21..0424212119 100644
--- a/Library/Homebrew/env_config.rb
+++ b/Library/Homebrew/env_config.rb
@@ -11,6 +11,11 @@ module Homebrew
     module_function
 
     ENVS = {
+      HOMEBREW_ALLOWED_TAPS:                     {
+        description: "A space-separated list of taps. Homebrew will refuse to install a " \
+                     "formula unless it and all of its dependencies are in an official tap " \
+                     "or in a tap on this list.",
+      },
       HOMEBREW_API_AUTO_UPDATE_SECS:             {
         description: "Check Homebrew's API for new formulae or cask data every " \
                      "`HOMEBREW_API_AUTO_UPDATE_SECS` seconds. Alternatively, disable API auto-update " \
diff --git a/Library/Homebrew/formula_installer.rb b/Library/Homebrew/formula_installer.rb
index d41673003e..21df0a776c 100644
--- a/Library/Homebrew/formula_installer.rb
+++ b/Library/Homebrew/formula_installer.rb
@@ -1391,15 +1391,7 @@ on_request: installed_on_request?, options:)
 
   sig { void }
   def forbidden_tap_check
-    forbidden_taps = Homebrew::EnvConfig.forbidden_taps
-    return if forbidden_taps.blank?
-
-    forbidden_taps_set = Set.new(forbidden_taps.split.filter_map do |tap|
-      Tap.fetch(tap)
-    rescue Tap::InvalidNameError
-      opoo "Invalid tap name in `HOMEBREW_FORBIDDEN_TAPS`: #{tap}"
-      nil
-    end)
+    return if Tap.allowed_taps.blank? && Tap.forbidden_taps.blank?
 
     owner = Homebrew::EnvConfig.forbidden_owner
     owner_contact = if (contact = Homebrew::EnvConfig.forbidden_owner_contact.presence)
@@ -1409,26 +1401,32 @@ on_request: installed_on_request?, options:)
     unless ignore_deps?
       compute_dependencies.each do |(dep, _options)|
         dep_tap = dep.tap
-        next if dep_tap.blank?
-        next unless forbidden_taps_set.include?(dep_tap)
+        next if dep_tap.blank? || (dep_tap.allowed_by_env? && !dep_tap.forbidden_by_env?)
 
-        raise CannotInstallFormulaError, <<~EOS
-          The installation of #{formula.name} has a dependency #{dep.name}
-          but the #{dep_tap} tap was forbidden by #{owner} in `HOMEBREW_FORBIDDEN_TAPS`.#{owner_contact}
-        EOS
+        error_message = +"The installation of #{formula.name} has a dependency #{dep.name}\n" \
+                         "from the #{dep_tap} tap but #{owner} "
+        error_message << "has not allowed this tap in `HOMEBREW_ALLOWED_TAPS`" unless dep_tap.allowed_by_env?
+        error_message << " and\n" if !dep_tap.allowed_by_env? && dep_tap.forbidden_by_env?
+        error_message << "has forbidden this tap in `HOMEBREW_FORBIDDEN_TAPS`" if dep_tap.forbidden_by_env?
+        error_message << ".#{owner_contact}"
+
+        raise CannotInstallFormulaError, error_message
       end
     end
 
     return if only_deps?
 
     formula_tap = formula.tap
-    return if formula_tap.blank?
-    return unless forbidden_taps_set.include?(formula_tap)
+    return if formula_tap.blank? || (formula_tap.allowed_by_env? && !formula_tap.forbidden_by_env?)
 
-    raise CannotInstallFormulaError, <<~EOS
-      The installation of #{formula.full_name} has the tap #{formula_tap}
-      which was forbidden by #{owner} in `HOMEBREW_FORBIDDEN_TAPS`.#{owner_contact}
-    EOS
+    error_message = +"The installation of #{formula.full_name} has the tap #{formula_tap}\n" \
+                     "but #{owner} "
+    error_message << "has not allowed this tap in `HOMEBREW_ALLOWED_TAPS`" unless formula_tap.allowed_by_env?
+    error_message << " and\n" if !formula_tap.allowed_by_env? && formula_tap.forbidden_by_env?
+    error_message << "has forbidden this tap in `HOMEBREW_FORBIDDEN_TAPS`" if formula_tap.forbidden_by_env?
+    error_message << ".#{owner_contact}"
+
+    raise CannotInstallFormulaError, error_message
   end
 
   sig { void }
diff --git a/Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi b/Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi
index 938cd076f0..e6a1945bbe 100644
--- a/Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi
+++ b/Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi
@@ -9,6 +9,9 @@ module Homebrew::EnvConfig
     sig { returns(T.nilable(::String)) }
     def all_proxy; end
 
+    sig { returns(T.nilable(::String)) }
+    def allowed_taps; end
+
     sig { returns(Integer) }
     def api_auto_update_secs; end
 
diff --git a/Library/Homebrew/tap.rb b/Library/Homebrew/tap.rb
index 183bc7ffe4..1577624988 100644
--- a/Library/Homebrew/tap.rb
+++ b/Library/Homebrew/tap.rb
@@ -132,6 +132,36 @@ class Tap
     false
   end
 
+  sig { returns(T::Set[Tap]) }
+  def self.allowed_taps
+    cache_key = :"allowed_taps_#{Homebrew::EnvConfig.allowed_taps.to_s.tr(" ", "_")}"
+    cache[cache_key] ||= begin
+      allowed_tap_list = Homebrew::EnvConfig.allowed_taps.to_s.split
+
+      Set.new(allowed_tap_list.filter_map do |tap|
+        Tap.fetch(tap)
+      rescue Tap::InvalidNameError
+        opoo "Invalid tap name in `HOMEBREW_ALLOWED_TAPS`: #{tap}"
+        nil
+      end).freeze
+    end
+  end
+
+  sig { returns(T::Set[Tap]) }
+  def self.forbidden_taps
+    cache_key = :"forbidden_taps_#{Homebrew::EnvConfig.forbidden_taps.to_s.tr(" ", "_")}"
+    cache[cache_key] ||= begin
+      forbidden_tap_list = Homebrew::EnvConfig.forbidden_taps.to_s.split
+
+      Set.new(forbidden_tap_list.filter_map do |tap|
+        Tap.fetch(tap)
+      rescue Tap::InvalidNameError
+        opoo "Invalid tap name in `HOMEBREW_FORBIDDEN_TAPS`: #{tap}"
+        nil
+      end).freeze
+    end
+  end
+
   # @api public
   extend Enumerable
 
@@ -1056,6 +1086,20 @@ class Tap
     end
   end
 
+  sig { returns(T::Boolean) }
+  def allowed_by_env?
+    @allowed_by_env ||= begin
+      allowed_taps = self.class.allowed_taps
+
+      official? || allowed_taps.blank? || allowed_taps.include?(self)
+    end
+  end
+
+  sig { returns(T::Boolean) }
+  def forbidden_by_env?
+    @forbidden_by_env ||= self.class.forbidden_taps.include?(self)
+  end
+
   private
 
   sig { params(file: Pathname).returns(T.any(T::Array[String], Hash)) }
diff --git a/Library/Homebrew/test/cask/installer_spec.rb b/Library/Homebrew/test/cask/installer_spec.rb
index 031b9d4a99..568d848909 100644
--- a/Library/Homebrew/test/cask/installer_spec.rb
+++ b/Library/Homebrew/test/cask/installer_spec.rb
@@ -326,22 +326,48 @@ RSpec.describe Cask::Installer, :cask do
   end
 
   describe "#forbidden_tap_check" do
-    it "raises on forbidden tap on cask" do
-      ENV["HOMEBREW_FORBIDDEN_TAPS"] = tap = "homebrew/forbidden"
+    before do
+      allow(Tap).to receive_messages(allowed_taps: allowed_taps_set, forbidden_taps: forbidden_taps_set)
+    end
 
-      cask = Cask::Cask.new("homebrew-forbidden-tap", tap: Tap.fetch(tap)) do
+    let(:homebrew_forbidden) { Tap.fetch("homebrew/forbidden") }
+    let(:allowed_third_party) { Tap.fetch("nothomebrew/allowed") }
+    let(:disallowed_third_party) { Tap.fetch("nothomebrew/notallowed") }
+    let(:allowed_taps_set) { Set.new([allowed_third_party]) }
+    let(:forbidden_taps_set) { Set.new([homebrew_forbidden]) }
+
+    it "raises on forbidden tap on cask" do
+      cask = Cask::Cask.new("homebrew-forbidden-tap", tap: homebrew_forbidden) do
         url "file://#{TEST_FIXTURE_DIR}/cask/container.tar.gz"
       end
 
       expect do
         described_class.new(cask).forbidden_tap_check
-      end.to raise_error(Cask::CaskCannotBeInstalledError, /has the tap #{tap}/)
+      end.to raise_error(Cask::CaskCannotBeInstalledError, /has the tap #{homebrew_forbidden}/)
+    end
+
+    it "raises on not allowed third-party tap on cask" do
+      cask = Cask::Cask.new("homebrew-not-allowed-tap", tap: disallowed_third_party) do
+        url "file://#{TEST_FIXTURE_DIR}/cask/container.tar.gz"
+      end
+
+      expect do
+        described_class.new(cask).forbidden_tap_check
+      end.to raise_error(Cask::CaskCannotBeInstalledError, /has the tap #{disallowed_third_party}/)
+    end
+
+    it "does not raise on allowed tap on cask" do
+      cask = Cask::Cask.new("third-party-allowed-tap", tap: allowed_third_party) do
+        url "file://#{TEST_FIXTURE_DIR}/cask/container.tar.gz"
+      end
+
+      expect { described_class.new(cask).forbidden_tap_check }.not_to raise_error
     end
 
     it "raises on forbidden tap on dependency" do
-      ENV["HOMEBREW_FORBIDDEN_TAPS"] = dep_tap = "homebrew/forbidden"
+      dep_tap = homebrew_forbidden
       dep_name = "homebrew-forbidden-dependency-tap"
-      dep_path = Tap.fetch(dep_tap).new_formula_path(dep_name)
+      dep_path = dep_tap.new_formula_path(dep_name)
       dep_path.parent.mkpath
       dep_path.write <<~RUBY
         class #{Formulary.class_s(dep_name)} < Formula
@@ -358,7 +384,7 @@ RSpec.describe Cask::Installer, :cask do
 
       expect do
         described_class.new(cask).forbidden_tap_check
-      end.to raise_error(Cask::CaskCannotBeInstalledError, /but the #{dep_tap} tap was forbidden/)
+      end.to raise_error(Cask::CaskCannotBeInstalledError, /from the #{dep_tap} tap but/)
     ensure
       dep_path.parent.parent.rmtree
     end
diff --git a/Library/Homebrew/test/formula_installer_spec.rb b/Library/Homebrew/test/formula_installer_spec.rb
index e8be7f7cbb..e2655cd0c5 100644
--- a/Library/Homebrew/test/formula_installer_spec.rb
+++ b/Library/Homebrew/test/formula_installer_spec.rb
@@ -258,10 +258,20 @@ RSpec.describe FormulaInstaller do
   end
 
   describe "#forbidden_tap_check" do
+    before do
+      allow(Tap).to receive_messages(allowed_taps: allowed_taps_set, forbidden_taps: forbidden_taps_set)
+    end
+
+    let(:homebrew_forbidden) { Tap.fetch("homebrew/forbidden") }
+    let(:allowed_third_party) { Tap.fetch("nothomebrew/allowed") }
+    let(:disallowed_third_party) { Tap.fetch("nothomebrew/notallowed") }
+    let(:allowed_taps_set) { Set.new([allowed_third_party]) }
+    let(:forbidden_taps_set) { Set.new([homebrew_forbidden]) }
+
     it "raises on forbidden tap on formula" do
-      ENV["HOMEBREW_FORBIDDEN_TAPS"] = f_tap = "homebrew/forbidden"
+      f_tap = homebrew_forbidden
       f_name = "homebrew-forbidden-tap"
-      f_path = Tap.fetch(f_tap).new_formula_path(f_name)
+      f_path = homebrew_forbidden.new_formula_path(f_name)
       f_path.parent.mkpath
       f_path.write <<~RUBY
         class #{Formulary.class_s(f_name)} < Formula
@@ -281,10 +291,54 @@ RSpec.describe FormulaInstaller do
       f_path.parent.parent.rmtree
     end
 
+    it "raises on not allowed third-party tap on formula" do
+      f_tap = disallowed_third_party
+      f_name = "homebrew-not-allowed-tap"
+      f_path = disallowed_third_party.new_formula_path(f_name)
+      f_path.parent.mkpath
+      f_path.write <<~RUBY
+        class #{Formulary.class_s(f_name)} < Formula
+          url "foo"
+          version "0.1"
+        end
+      RUBY
+      Formulary.cache.delete(f_path)
+
+      f = Formulary.factory("#{f_tap}/#{f_name}")
+      fi = described_class.new(f)
+
+      expect do
+        fi.forbidden_tap_check
+      end.to raise_error(CannotInstallFormulaError, /has the tap #{f_tap}/)
+    ensure
+      f_path.parent.parent.parent.rmtree
+    end
+
+    it "does not raise on allowed tap on formula" do
+      f_tap = allowed_third_party
+      f_name = "homebrew-allowed-tap"
+      f_path = allowed_third_party.new_formula_path(f_name)
+      f_path.parent.mkpath
+      f_path.write <<~RUBY
+        class #{Formulary.class_s(f_name)} < Formula
+          url "foo"
+          version "0.1"
+        end
+      RUBY
+      Formulary.cache.delete(f_path)
+
+      f = Formulary.factory("#{f_tap}/#{f_name}")
+      fi = described_class.new(f)
+
+      expect { fi.forbidden_tap_check }.not_to raise_error
+    ensure
+      f_path.parent.parent.parent.rmtree
+    end
+
     it "raises on forbidden tap on dependency" do
-      ENV["HOMEBREW_FORBIDDEN_TAPS"] = dep_tap = "homebrew/forbidden"
+      dep_tap = homebrew_forbidden
       dep_name = "homebrew-forbidden-dependency-tap"
-      dep_path = Tap.fetch(dep_tap).new_formula_path(dep_name)
+      dep_path = homebrew_forbidden.new_formula_path(dep_name)
       dep_path.parent.mkpath
       dep_path.write <<~RUBY
         class #{Formulary.class_s(dep_name)} < Formula
@@ -310,7 +364,7 @@ RSpec.describe FormulaInstaller do
 
       expect do
         fi.forbidden_tap_check
-      end.to raise_error(CannotInstallFormulaError, /but the #{dep_tap} tap was forbidden/)
+      end.to raise_error(CannotInstallFormulaError, /from the #{dep_tap} tap but/)
     ensure
       dep_path.parent.parent.rmtree
     end
diff --git a/Library/Homebrew/test/tap_spec.rb b/Library/Homebrew/test/tap_spec.rb
index a8cafb6799..940ac944f9 100644
--- a/Library/Homebrew/test/tap_spec.rb
+++ b/Library/Homebrew/test/tap_spec.rb
@@ -142,6 +142,24 @@ RSpec.describe Tap do
     end
   end
 
+  describe "::allowed_taps" do
+    before { allow(Homebrew::EnvConfig).to receive(:allowed_taps).and_return("homebrew/allowed") }
+
+    it "returns a set of allowed taps according to the environment" do
+      expect(described_class.allowed_taps)
+        .to contain_exactly(described_class.fetch("homebrew/allowed"))
+    end
+  end
+
+  describe "::forbidden_taps" do
+    before { allow(Homebrew::EnvConfig).to receive(:forbidden_taps).and_return("homebrew/forbidden") }
+
+    it "returns a set of forbidden taps according to the environment" do
+      expect(described_class.forbidden_taps)
+        .to contain_exactly(described_class.fetch("homebrew/forbidden"))
+    end
+  end
+
   specify "::names" do
     expect(described_class.names.sort).to eq(["homebrew/core", "homebrew/foo"])
   end