diff --git a/autoload/highlight.vim b/autoload/highlight.vim
index 34cb426..e8f7b3f 100644
--- a/autoload/highlight.vim
+++ b/autoload/highlight.vim
@@ -35,10 +35,10 @@ let s:registry = {}
 " Convenience method to determine which register is being currently used.
 " The unnamed register defaults to the last used register to avoid having to
 " constantly prefix registration. This can be changed by setting the value of
-" g:persist_unnamed_register to 1.
+" g:highlight_persist_unnamed_register to 1.
 
 function! highlight#expand_reg(reg)
-  if !g:persist_unnamed_register && a:reg ==# '"'
+  if !g:highlight_persist_unnamed_register && a:reg ==# '"'
     return s:active_register
   endif
   return a:reg
diff --git a/plugin/hightlight.vim b/plugin/hightlight.vim
index c35151e..21d40c7 100644
--- a/plugin/hightlight.vim
+++ b/plugin/hightlight.vim
@@ -45,13 +45,24 @@ if !exists('g:highlight_registry')
 endif
 
 
-" g:persist_unnamed_register :: Boolean {{{2
+" g:highlight_persist_unnamed_register :: Boolean {{{2
 " ------------------------------------------------------------------------------
 " Determines how to manage the unnamed register '"'. If set to false, we regard
 " the unnamed register to implicitly imply use of the last activated register.
 
-if !exists('g:persist_unnamed_register')
-  let g:persist_unnamed_register = 0
+if !exists('g:highlight_persist_unnamed_register')
+  let g:highlight_persist_unnamed_register = 0
+endif
+
+
+" g:highlight_register_prefix :: String {{{2
+" ------------------------------------------------------------------------------
+" Prefix used for group names and for link between Search highlight group and
+" the highlight registries. That is, hi link Search {g:highlight_register_prefix}
+" and hi link {g:highlight_register_prefix} {active search register}.
+
+if !exists('g:highlight_register_prefix')
+  let g:highlight_register_prefix = 'HighlightRegister'
 endif