diff --git a/CMakeLists.txt b/CMakeLists.txt
index 203c5d2..055bd0e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -640,9 +640,9 @@
   set(CERES_DOCS_INSTALL_DIR "share/doc/ceres" CACHE STRING
       "Ceres docs install path relative to CMAKE_INSTALL_PREFIX")
 
-  find_package(Sphinx QUIET)
+  find_package(Sphinx)
   if (NOT SPHINX_FOUND)
-    message("-- Failed to find Sphinx, disabling build of documentation.")
+    message("-- Failed to find Sphinx and/or its dependencies, disabling build of documentation.")
     update_cache_variable(BUILD_DOCUMENTATION OFF)
   else()
     # Generate the User's Guide (html).
diff --git a/cmake/FindSphinx.cmake b/cmake/FindSphinx.cmake
index 220108d..2ba3c81 100644
--- a/cmake/FindSphinx.cmake
+++ b/cmake/FindSphinx.cmake
@@ -43,24 +43,30 @@
                /opt/local/bin
              DOC "Sphinx documentation generator")
 
-if (NOT SPHINX_EXECUTABLE)
-  set(_Python_VERSIONS 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.6 1.5)
+if (SPHINX_EXECUTABLE)
 
-  foreach (_version ${_Python_VERSIONS})
-    set(_sphinx_NAMES sphinx-build-${_version})
+  find_package(PythonInterp 3)
 
-    find_program(SPHINX_EXECUTABLE
-                 NAMES ${_sphinx_NAMES}
-                 PATHS
-                   /usr/bin
-                   /usr/local/bin
-                   /opt/local/bin
-                 DOC "Sphinx documentation generator")
-  endforeach ()
+  if(PYTHONINTERP_FOUND)
+    # Check for sphinx theme dependency for documentation
+    execute_process(
+      COMMAND ${PYTHON_EXECUTABLE} -m pip show sphinx-rtd-theme
+      RESULT_VARIABLE SPHINX_RTD_THEME
+      OUTPUT_QUIET
+      ERROR_QUIET
+    )
+  endif ()
+
+  if (${SPHINX_RTD_THEME} EQUAL 0)
+    set(SPHINX_RTD_THEME TRUE)
+  else ()
+    set(SPHINX_RTD_THEME FALSE)
+  endif ()
+
 endif ()
 
 include(FindPackageHandleStandardArgs)
 
-find_package_handle_standard_args(Sphinx DEFAULT_MSG SPHINX_EXECUTABLE)
+find_package_handle_standard_args(Sphinx DEFAULT_MSG SPHINX_EXECUTABLE SPHINX_RTD_THEME)
 
 mark_as_advanced(SPHINX_EXECUTABLE)
diff --git a/docs/source/CMakeLists.txt b/docs/source/CMakeLists.txt
index 70bf998..217a519 100644
--- a/docs/source/CMakeLists.txt
+++ b/docs/source/CMakeLists.txt
@@ -9,9 +9,12 @@
         COMPONENT Doc
         PATTERN "${SPHINX_HTML_DIR}/*")
 
+# Find python 3
+find_package(PythonInterp 3 REQUIRED)
+
 # Building using 'make_docs.py' python script
 add_custom_target(ceres_docs ALL
-                  python
+                  ${PYTHON_EXECUTABLE}
                   "${Ceres_SOURCE_DIR}/scripts/make_docs.py"
                   "${Ceres_SOURCE_DIR}"
                   "${Ceres_BINARY_DIR}/docs"