diff --git a/confluence-api-client.gemspec b/confluence-api-client.gemspec
index 8a8490f..e0775fb 100644
--- a/confluence-api-client.gemspec
+++ b/confluence-api-client.gemspec
@@ -22,9 +22,13 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_development_dependency "bundler", "~> 1.8"
+  spec.add_development_dependency "bundler", "~> 2.1"
   spec.add_development_dependency "rake", "~> 10.0"
+  spec.add_development_dependency "rspec-core"
+  spec.add_development_dependency "rspec-expectations"
+  spec.add_development_dependency "rspec-mocks"
 
   spec.add_runtime_dependency "json"
   spec.add_runtime_dependency "faraday"
+  spec.add_runtime_dependency "mime-types"
 end
diff --git a/lib/confluence/api/client.rb b/lib/confluence/api/client.rb
index 128b68b..555dc27 100644
--- a/lib/confluence/api/client.rb
+++ b/lib/confluence/api/client.rb
@@ -1,22 +1,18 @@
 require "confluence/api/client/version"
 require 'json'
 require 'faraday'
+require 'securerandom'
+require 'mime/types'
 
 module Confluence
   module Api
     class Client
-      attr_accessor :user, :pass, :url, :conn
+      attr_accessor :user, :pass, :url
 
       def initialize(user, pass, url)
         self.user = user
         self.pass = pass
         self.url  = url
-        self.conn = Faraday.new(url: url) do |faraday|
-          faraday.request :url_encoded # form-encode POST params
-          # faraday.response :logger                  # log requests to STDOUT
-          faraday.adapter Faraday.default_adapter # make requests with Net::HTTP
-          faraday.basic_auth(self.user, self.pass)
-        end
       end
 
       def get(params)
@@ -47,6 +43,66 @@ def update(id, params)
         JSON.parse(response.body)
       end
 
+      def create_attachment(page_id, file_info, comment=nil)
+        sep = SecureRandom.hex(8)
+        file = resolve_file_info_from(file_info)
+        boundary = "-----------------------#{ sep }"
+
+        file_section = [
+          "Content-Disposition: form-data; name=\"file\"; filename=\"#{ file[:name] }\"",
+          "Content-Type: #{ file[:type] }",
+          "",
+          file[:content],
+          ""
+        ].join("\r\n")
+
+        content = "--#{ boundary }\r\n"
+        content << file_section  
+        if comment
+          content << "--#{ boundary }\r\n"
+          comment_section = [
+            "Content-Disposition: form-data; name=\"comment\"",
+            "",
+            comment,
+            ""
+          ].join("\r\n")
+          content << comment_section
+        end
+        content << "--#{ boundary }--\r\n"
+
+        response = conn.post do |request|
+          request.headers['content-type'] = "multipart/form-data; boundary=#{ boundary }"
+          request.headers['X-Atlassian-Token'] = 'nocheck'
+          url = "rest/api/content/#{ page_id }/child/attachment"
+          request.url url
+          request.body = content
+        end
+
+        [response.status == 200 ? :ok : :error, JSON.parse(response.body)]
+      end
+
+      private
+
+      def resolve_file_info_from file_info
+        return file_info if file_info.kind_of?(Hash)
+
+        file_name = file_info.split('/').last
+
+        {
+          name: file_name,
+          type: MIME::Types.type_for(file_name).first,
+          content: File.open(file_info).read
+        }
+      end
+
+      def conn
+        @conn ||= Faraday.new(url: url) do |faraday|
+          faraday.request :url_encoded # form-encode POST params
+          # faraday.response :logger                  # log requests to STDOUT
+          faraday.adapter Faraday.default_adapter # make requests with Net::HTTP
+          faraday.basic_auth(user, pass)
+        end
+      end
     end
   end
 end
diff --git a/spec/confluence/api/client_spec.rb b/spec/confluence/api/client_spec.rb
index cf2387c..f664bbb 100644
--- a/spec/confluence/api/client_spec.rb
+++ b/spec/confluence/api/client_spec.rb
@@ -5,7 +5,114 @@
     expect(Confluence::Api::Client::VERSION).not_to be nil
   end
 
-  it 'does something useful' do
-    expect(false).to eq(true)
+  describe 'instance methods' do
+    subject(:instance) { described_class.new(user, pass, url) }
+    let(:user) { 'confluence-user-identifier' }
+    let(:pass) { 'confluence-api-key' }
+    let(:url) { 'confluence-url' }
+
+    let(:dummy_connection) { double(:connection) }
+    let(:dummy_request) { double(:request, headers: {}) } 
+
+    describe '#create_attachment' do
+      let(:page_id) { 1234 }
+      let(:random_hex) { 'deadbeefdeadbeef' }
+      let(:comment) { nil }
+
+      before :each do
+        allow(instance).to receive(:conn).and_return(dummy_connection)
+        allow(dummy_connection).to receive(:post).and_yield(dummy_request)
+        allow(SecureRandom).to receive(:hex).with(8).and_return(random_hex)
+        allow(dummy_request).to receive(:url)
+        allow(dummy_request).to receive(:body=)
+
+        if comment.nil?
+          instance.create_attachment(page_id, file_info)
+        else
+          instance.create_attachment(page_id, file_info, comment)
+        end
+      end
+
+      context 'using a filename to identify the file' do
+        let(:file_info) { File.expand_path('../../../fixtures/example.txt',  __FILE__) }
+        let(:expected_content) do
+          <<-TEXT
+-------------------------deadbeefdeadbeef\r
+Content-Disposition: form-data; name="file"; filename="example.txt"\r
+Content-Type: text/plain\r
+\r
+This is a simple example text file.\r
+-------------------------deadbeefdeadbeef--\r
+          TEXT
+        end
+
+        it 'submits what is expected' do
+          expect(dummy_connection).to have_received(:post)
+          expect(dummy_request.headers).to eq({
+            'content-type' => "multipart/form-data; boundary=-----------------------#{ random_hex }",
+            'X-Atlassian-Token' => 'nocheck'
+          })
+          expect(dummy_request).to have_received(:url).with("rest/api/content/#{ page_id }/child/attachment")
+          expect(dummy_request).to have_received(:body=).with expected_content
+        end
+
+        context 'and it includes a comment' do
+          let(:comment) { 'Silly Little Comment' }
+
+          let(:expected_content) do
+            <<-TEXT
+-------------------------deadbeefdeadbeef\r
+Content-Disposition: form-data; name="file"; filename="example.txt"\r
+Content-Type: text/plain\r
+\r
+This is a simple example text file.\r
+-------------------------deadbeefdeadbeef\r
+Content-Disposition: form-data; name="comment"\r
+\r
+Silly Little Comment\r
+-------------------------deadbeefdeadbeef--\r
+            TEXT
+          end
+  
+          it 'submits what is expected' do
+            expect(dummy_request).to have_received(:body=).with expected_content
+          end
+        end
+      end
+
+      context 'using a hash to identify the file' do
+        let(:file_info) do
+          {
+            name: 'sample.txt',
+            type: 'text/plain',
+            content: <<-CONTENT
+This is some lovely LOVELY content.
+            CONTENT
+          }
+        end
+
+        let(:expected_content) do
+          <<-TEXT
+-------------------------deadbeefdeadbeef\r
+Content-Disposition: form-data; name="file"; filename="sample.txt"\r
+Content-Type: text/plain\r
+\r
+This is some lovely LOVELY content.
+\r
+-------------------------deadbeefdeadbeef--\r
+          TEXT
+        end
+
+        it 'submits what is expected' do
+          expect(dummy_connection).to have_received(:post)
+          expect(dummy_request.headers).to eq({
+            'content-type' => "multipart/form-data; boundary=-----------------------#{ random_hex }",
+            'X-Atlassian-Token' => 'nocheck'
+          })
+          expect(dummy_request).to have_received(:url).with("rest/api/content/#{ page_id }/child/attachment")
+          expect(dummy_request).to have_received(:body=).with expected_content
+        end
+      end
+    end
   end
 end
diff --git a/spec/fixtures/example.csv b/spec/fixtures/example.csv
new file mode 100644
index 0000000..7fba8c5
--- /dev/null
+++ b/spec/fixtures/example.csv
@@ -0,0 +1,4 @@
+First,Second,Third
+a,b,c
+1,2,3
+x,y,z
\ No newline at end of file
diff --git a/spec/fixtures/example.txt b/spec/fixtures/example.txt
new file mode 100644
index 0000000..7be5f07
--- /dev/null
+++ b/spec/fixtures/example.txt
@@ -0,0 +1 @@
+This is a simple example text file.
\ No newline at end of file