diff --git a/docs/user-guide/cli.md b/docs/user-guide/cli.md
index ff16c762..c21e0931 100644
--- a/docs/user-guide/cli.md
+++ b/docs/user-guide/cli.md
@@ -139,12 +139,19 @@ ELB failures which will result in instance replacements.
 
 ## `moonshot update`
 
-Update an environment with the latest local CloudFormation template,
-and any Parameter updates specified via `--answer-file` or
-`--parameter`. If there are new parameters in the template and they
-are not specified, the user will be prompted for their values, unless
-`--no-interactive` is specified, in which case an error will be
-displayed.
+Update an environment with the latest local CloudFormation template
+using a ChangeSet. Keep all existing parameters, unless they are
+specified by `--answer-file` and/or `--parameter`. If there are new
+parameters in the template and they are not specified, the user will
+be prompted for their values, unless `--no-interactive` is specified,
+in which case an error will be displayed.
+
+The user is prompted interactively to accept the ChangeSet, unless
+`--no-interactive` is set. `--force` can be specified to automatically
+accept the changes. If `--dry-run` is set, the changes are
+automatically rejected after being displayed, which can be useful for
+seeing what the impact of a template change might be in a given
+environment.
 
 ### Options
 
@@ -164,6 +171,17 @@ See [create][#moonshot-create].
 
 See [create][#moonshot-create].
 
+#### `--force`
+
+Automatically accept the ChangeSet that was generated, without
+prompting the user. The changes are still displayed in the log
+output.
+
+#### `--dry-run`
+
+Automatically reject the ChangeSet that was generated, after
+displaying the changes.
+
 ### Examples
 
 Update a single Stack parameter, using the latest template:
diff --git a/docs/user-guide/stack_parameter_strategies.md b/docs/user-guide/stack_parameter_strategies.md
deleted file mode 100644
index 7de1ca2e..00000000
--- a/docs/user-guide/stack_parameter_strategies.md
+++ /dev/null
@@ -1,95 +0,0 @@
-# Stack Parameter strategies
-
-Currently used, valid strategy types are:
-- `default`
-- `merge`
-
-Strategy type can be set both via command line, or overriding
-the default behaviour in your `Moonshot::CLI` subclass.
-
-**Command line:** `bin/environment update --parameter-strategy=merge`
-
-**Inline:** `parameter_strategy :merge`
-
-Accepted both as a string or a symbol.
-
-Setting precedence is the following:
-- command line option
-- inline default behaviour override
-- falling back to `default`
-
-## Default strategy
-
-Default strategy is the legacy behaviour, works exactly as previously,
-prior to introducing different strategies. Each parameter is loaded from the
-parameter file (eg. `cloud_formation/parameters/environment-name.yml`),
-and *all of them* are overridden on update.
-
-**Word of caution:** when using this strategy we encourage you to keep all
-per-environment tunings in the source repository acting as both a safety net
-and documentation of existing environments. A possible solution for using this
-strategy in a safe manner is the following:
-
-When a stack update is performed, a *parameter file* is checked in
-`cloud_formation/parameters/environment-name.yml`. This file is YAML formatted
-and takes a hash of stack parameter names and values, for example:
-```yaml
----
-AsgDesiredCap: 12
-AsgMaxCap: 15
-ELBCertificate: iam::something:star_example_com
-```
-
-If a file exists, it's used every time a CloudFormation change request is sent,
-so no configuration can revert back to defaults through this tool. It's highly
-recommended that you add these files back to source control as soon as possible
-and be in the habit of pulling latest changes before applying any infrastructure
-updates.
-
-## Merge strategy
-
-Merge strategy is a new way of dealing with stack parameters on stack update.
-You only have to declare **parameters you want to update** in your parameter file,
-the remaining parameters are not updated, meaning it stays as it's current uploaded (live) state.
-This behaviour is achived by using CloudFormation's `UsePreviousValue` feature.
-This way you can avoid accidentally reverting parameter values with your outdated local
-parameter file.
-
-# Defining custom parameter strategy class
-Defining and using your own custom parameter strategy class is possible if you are
-using Moonshot without the provided CLI. A parameter strategy class is a class which responds
-to a method called `parameters`. It receives two parameters: the first contains a hash
-of the existing, currently deployed stack parameters, the second one (also a hash) contains
-the parameters defined in the parameters file. The method should return an array of
-hashes of the following format:
-
-```json
-{
-  parameter_key: key,
-  parameter_value: value,
-  use_previous_value: false
-}
-```
-
-You either supply a value for `parameter_value` or set
-`use_previous_value` to `true`, which leaves the parameter as it
-currently is.
-
-Example:
-
-```ruby
-class CustomStrategy
-  def parameters(parameters, stack_parameters, template)
-    parameters.map do |k, v|
-      {
-        parameter_key: k,
-        parameter_value: v,
-        use_previous_value: false
-      }
-    end
-  end
-end
-```
-
-In order to use your custom strategy class, set a new instance of your
-class to `ControllerConfig`'s `parameter_strategy` attribute.
diff --git a/lib/moonshot.rb b/lib/moonshot.rb
index 2c2ec8cb..1dc38f47 100644
--- a/lib/moonshot.rb
+++ b/lib/moonshot.rb
@@ -54,8 +54,6 @@ module Plugins
   'stack_config',
   'stack_lister',
   'stack_events_poller',
-  'merge_strategy',
-  'default_strategy',
   'ask_user_source',
   'always_use_default_source',
 
diff --git a/lib/moonshot/change_set.rb b/lib/moonshot/change_set.rb
new file mode 100644
index 00000000..b28ef859
--- /dev/null
+++ b/lib/moonshot/change_set.rb
@@ -0,0 +1,100 @@
+module Moonshot
+  class ChangeSet
+    attr_reader :name
+    attr_reader :stack_name
+
+    def initialize(name, stack_name)
+      @name = name
+      @stack_name = stack_name
+      @change_set = nil
+      @cf_client = Aws::CloudFormation::Client.new
+    end
+
+    def confirm?
+      unless Moonshot.config.interactive
+        raise 'Cannot confirm ChangeSet when interactive mode is disabled!'
+      end
+
+      loop do
+        print 'Apply changes? '
+        resp = gets.chomp.downcase
+
+        return true if resp == 'yes'
+        return false if resp == 'no'
+        puts "Please enter 'yes' or 'no'!"
+      end
+    end
+
+    def valid?
+      @change_set.status == 'CREATE_COMPLETE'
+    end
+
+    def invalid_reason
+      @change_set.status_reason
+    end
+
+    def display_changes
+      wait_for_change_set unless @change_set
+
+      @change_set.changes.map(&:resource_change).each do |c|
+        puts "* #{c.action} #{c.logical_resource_id} (#{c.resource_type})"
+
+        if c.replacement == 'True'
+          puts ' - Will be replaced'
+        elsif c.replacement == 'Conditional'
+          puts ' - May be replaced (Conditional)'
+        end
+
+        c.details.each do |d|
+          case d.change_source
+          when 'ResourceReference', 'ParameterReference'
+            puts " - Caused by #{d.causing_entity.blue} (#{d.change_source})"
+          when 'DirectModification'
+            puts " - Caused by template change (#{d.target.attribute}: #{d.target.name})"
+          end
+        end
+      end
+    end
+
+    def execute
+      wait_for_change_set unless @change_set
+      @cf_client.execute_change_set(
+        change_set_name: @name,
+        stack_name: @stack_name)
+    end
+
+    def delete
+      wait_for_change_set unless @change_set
+      @cf_client.delete_change_set(
+        change_set_name: @name,
+        stack_name: @stack_name)
+    rescue Aws::CloudFormation::Errors::InvalidChangeSetStatus
+      sleep 1
+      retry
+    end
+
+    # NOTE: At the time of this patch, AWS-SDK native Waiters do not
+    # have support for ChangeSets. Once they add this, we can make
+    # this code much better.
+    def wait_for_change_set
+      start = Time.now.to_i
+
+      loop do
+        resp = @cf_client.describe_change_set(
+          change_set_name: @name,
+          stack_name: @stack_name)
+
+        if %w(CREATE_COMPLETE FAILED).include?(resp.status)
+          @change_set = resp
+          return
+        end
+
+        if Time.now.to_i > start + 30
+          raise 'ChangeSet did not complete creation within 30 seconds!'
+        end
+
+        sleep 0.25 # http://bit.ly/1qY1ZXJ
+      end
+    end
+  end
+end
diff --git a/lib/moonshot/commands/update.rb b/lib/moonshot/commands/update.rb
index 337c7ae0..adb34b7b 100644
--- a/lib/moonshot/commands/update.rb
+++ b/lib/moonshot/commands/update.rb
@@ -8,22 +8,22 @@ class Update < Moonshot::Command
       self.usage = 'update [options]'
       self.description = 'Update the CloudFormation stack within an environment.'
 
-      def execute
-        controller.update
-      end
+      def parser
+        parser = super
 
-      private
+        parser.on('--dry-run', TrueClass, 'Show the changes that would be applied, but do not execute them') do |v| # rubocop:disable LineLength
+          @dry_run = v
+        end
 
-      def parameter_strategy_factory(value)
-        case value.to_sym
-        when :default
-          Moonshot::ParameterStrategy::DefaultStrategy.new
-        when :merge
-          Moonshot::ParameterStrategy::MergeStrategy.new
-        else
-          raise "Unknown parameter strategy: #{value}"
+        parser.on('--force', '-f', TrueClass, 'Apply ChangeSet without confirmation') do |v|
+          @force = v
         end
       end
+
+      def execute
+        @force = true unless Moonshot.config.interactive
+        controller.update(dry_run: @dry_run, force: @force)
+      end
     end
   end
 end
diff --git a/lib/moonshot/controller.rb b/lib/moonshot/controller.rb
index 358c9910..bbe2dc7c 100644
--- a/lib/moonshot/controller.rb
+++ b/lib/moonshot/controller.rb
@@ -71,7 +71,7 @@ def create # rubocop:disable AbcSize
       end
     end
 
-    def update # rubocop:disable AbcSize
+    def update(dry_run:, force:) # rubocop:disable AbcSize
       # Scan the template for all required parameters and configure
       # the ParameterCollection.
       @config.parameters = ParameterCollection.from_template(stack.template)
@@ -119,7 +119,7 @@ def update # rubocop:disable AbcSize
       end
 
       run_hook(:deploy, :pre_update)
-      stack.update
+      stack.update(dry_run: dry_run, force: force)
       run_hook(:deploy, :post_update)
       run_plugins(:post_update)
     end
diff --git a/lib/moonshot/controller_config.rb b/lib/moonshot/controller_config.rb
index f39e57f2..88acf58d 100644
--- a/lib/moonshot/controller_config.rb
+++ b/lib/moonshot/controller_config.rb
@@ -1,4 +1,3 @@
-require_relative 'default_strategy'
 require_relative 'ssh_config'
 require_relative 'task'
 require_relative 'ask_user_source'
diff --git a/lib/moonshot/default_strategy.rb b/lib/moonshot/default_strategy.rb
deleted file mode 100644
index 4aae997e..00000000
--- a/lib/moonshot/default_strategy.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-module Moonshot
-  module ParameterStrategy
-    # Default strategy: use parameter defined in the parameter file
-    class DefaultStrategy
-      def parameters(params, _, _)
-        params.map do |key, _|
-          {
-            parameter_key: key,
-            parameter_value: params[key],
-            use_previous_value: false
-          }
-        end
-      end
-    end
-  end
-end
diff --git a/lib/moonshot/merge_strategy.rb b/lib/moonshot/merge_strategy.rb
deleted file mode 100644
index ea9fbfde..00000000
--- a/lib/moonshot/merge_strategy.rb
+++ /dev/null
@@ -1,31 +0,0 @@
-require 'highline/import'
-require_relative 'unicode_table'
-
-module Moonshot
-  module ParameterStrategy
-    # Merge strategy: prefer parameter values defined in the parameter file,
-    # otherwise use the previously set value on the existing stack.
-    class MergeStrategy
-      def parameters(params, stack_params, template)
-        stack_keys = stack_params.keys.select do |k|
-          template.parameters.any? { |p| p.name == k }
-        end
-
-        (params.keys + stack_keys).uniq.map do |key|
-          if params[key]
-            {
-              parameter_key: key,
-              parameter_value: params[key],
-              use_previous_value: false
-            }
-          else
-            {
-              parameter_key: key,
-              use_previous_value: true
-            }
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/lib/moonshot/stack.rb b/lib/moonshot/stack.rb
index a0e38412..930318a5 100644
--- a/lib/moonshot/stack.rb
+++ b/lib/moonshot/stack.rb
@@ -7,6 +7,7 @@
 require_relative 'stack_output_printer'
 require_relative 'stack_asg_printer'
 require_relative 'unicode_table'
+require_relative 'change_set'
 require 'yaml'
 
 module Moonshot
@@ -44,22 +45,21 @@ def create
       should_wait ? wait_for_stack_state(:stack_create_complete, 'created') : true
     end
 
-    def update
+    def update(dry_run:, force:)
       raise "No stack found #{@name.blue}!" unless stack_exists?
 
-      should_wait = true
-      @ilog.start "Updating #{stack_name}." do |s|
-        if update_stack
-          s.success "Initiated update for #{stack_name}."
-        else
-          s.success 'No Stack update required.'
-          should_wait = false
-        end
+      change_set = ChangeSet.new(new_change_set, @name)
+      wait_for_change_set(change_set)
+      return unless change_set.valid?
+
+      if dry_run
+        change_set.display_changes
+      elsif !force
+        change_set.display_changes
+        change_set.confirm? || raise('ChangeSet rejected!')
       end
 
-      success = should_wait ? wait_for_stack_state(:stack_update_complete, 'updated') : true
-      raise 'Failed to update the CloudFormation Stack.' unless success
-      success
+      execute_change_set(change_set)
     end
 
     def delete
@@ -232,20 +232,23 @@ def create_stack
       raise 'You are not authorized to perform create_stack calls.'
     end
 
-    # @return [Boolean]
-    #   true if a stack update was required and initiated, false otherwise.
-    def update_stack
-      cf_client.update_stack(
+    def new_change_set
+      change_set_name = [
+        'moonshot',
+        @name,
+        Time.now.utc.to_i.to_s
+      ].join('-')
+
+      cf_client.create_change_set(
+        change_set_name: change_set_name,
+        description: "Moonshot update command for application '#{Moonshot.config.app_name}'",
         stack_name: @name,
         template_body: template.body,
         capabilities: ['CAPABILITY_IAM'],
         parameters: @config.parameters.values.map(&:to_cf)
       )
-      true
-    rescue Aws::CloudFormation::Errors::ValidationError => e
-      raise e.message unless
-        e.message == 'No updates are to be performed.'
-      false
+
+      change_set_name
     end
 
     # TODO: Refactor this into it's own class.
@@ -335,5 +338,28 @@ def doctor_check_template_against_aws
     rescue => e
       critical('Invalid CloudFormation template!', e.message)
     end
+
+    def wait_for_change_set(change_set)
+      @ilog.start_threaded "Waiting for ChangeSet #{change_set.name.blue} to be created." do |s|
+        change_set.wait_for_change_set
+
+        if change_set.valid?
+          s.success "ChangeSet #{change_set.name.blue} ready!"
+        else
+          s.failure "ChangeSet failed to create: #{change_set.invalid_reason}"
+        end
+      end
+    end
+
+    def execute_change_set(change_set)
+      @ilog.start_threaded "Executing ChangeSet #{change_set.name.blue} for #{stack_name}." do |s|
+        change_set.execute
+        s.success "Executed ChangeSet #{change_set.name.blue} for #{stack_name}."
+      end
+
+      success = wait_for_stack_state(:stack_update_complete, 'updated')
+      raise 'Failed to update the CloudFormation Stack.' unless success
+      success
+    end
   end
 end
diff --git a/lib/moonshot/stack_config.rb b/lib/moonshot/stack_config.rb
index 9378ae1f..7093ce1a 100644
--- a/lib/moonshot/stack_config.rb
+++ b/lib/moonshot/stack_config.rb
@@ -3,7 +3,6 @@ module Moonshot
   class StackConfig
     attr_accessor :parent_stacks
     attr_accessor :show_all_events
-    attr_accessor :parameter_strategy
 
     def initialize
       @parent_stacks = []
diff --git a/mkdocs.yml b/mkdocs.yml
index 815428fe..9fff98f0 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -7,7 +7,6 @@ pages:
   - 'CLI Commands': 'user-guide/cli.md'
   - 'Including Moonshot in your project': 'user-guide/include_in_your_project.md'
   - 'Working with parent stacks': 'user-guide/parent_stacks.md'
-  - 'Stack parameter strategies': 'user-guide/stack_parameter_strategies.md'
 - Mechanisms:
   - 'Artifact Repository': 'mechanisms/artifact-repository.md'
   - 'Build': 'mechanisms/build.md'
diff --git a/spec/moonshot/controller_spec.rb b/spec/moonshot/controller_spec.rb
index 9a12282a..914c3e89 100644
--- a/spec/moonshot/controller_spec.rb
+++ b/spec/moonshot/controller_spec.rb
@@ -152,7 +152,7 @@
       expect(stack).to receive(:parameters).and_return(existing_parameters)
       expect(stack).to receive(:update)
 
-      subject.update
+      subject.update(dry_run: false, force: false)
 
       pc = subject.config.parameters
       expect(pc.keys).to eq(%w(InputParameter1 InputParameter2 InputParameter3 InputParameter4))
diff --git a/spec/moonshot/merge_strategy_spec.rb b/spec/moonshot/merge_strategy_spec.rb
deleted file mode 100644
index f592c768..00000000
--- a/spec/moonshot/merge_strategy_spec.rb
+++ /dev/null
@@ -1,80 +0,0 @@
-describe Moonshot::ParameterStrategy::MergeStrategy do
-  subject { described_class.new }
-
-  describe '#parameters' do
-    subject do
-      super().parameters(
-        parameters,
-        stack_parameters,
-        template
-      )
-    end
-
-    let(:parameters) do
-      {
-        file_parameter_1: 'file_parameter_1',
-        file_parameter_2: 'file_parameter_2'
-      }
-    end
-
-    let(:stack_parameters) do
-      {
-        stack_parameter_1: 'stack_parameter_1',
-        stack_parameter_2: 'stack_parameter_2'
-      }
-    end
-
-    let(:template_parameters) do
-      [
-        double('template_param', name: :stack_parameter_1),
-        double('template_param', name: :stack_parameter_2)
-      ]
-    end
-
-    let(:template) do
-      template = double(Moonshot::StackTemplate)
-      allow(template).to receive(:parameters).and_return(template_parameters)
-      template
-    end
-
-    let(:actual_keys) do
-      subject.map { |p| p[:parameter_key] }
-    end
-
-    it 'includes the stack and YAML file parameters' do
-      expected_keys = (parameters.keys + stack_parameters.keys).uniq
-      expect(actual_keys).to eq(expected_keys)
-    end
-
-    context 'when the template no longer includes a stack parameter' do
-      let(:removed_element) do
-        template_parameters.pop
-      end
-
-      it 'does not include the removed parameter' do
-        removed_key = removed_element.name
-        expect(actual_keys).not_to include(removed_key)
-      end
-    end
-
-    context 'when the template adds a new parameter and it is provided' do
-      let(:added_parameter) do
-        double('template_param', name: :template_parameter_1)
-      end
-
-      let(:template_parameters) do
-        super().insert(added_parameter)
-      end
-
-      let(:parameters) do
-        parameters = super()
-        parameters[added_parameter.name] = 'template_parameter_1'
-        parameters
-      end
-
-      it 'includes the added parameter' do
-        expect(actual_keys).to include(added_parameter.name)
-      end
-    end
-  end
-end