diff --git a/src/apply/ref.xsl b/src/apply/ref.xsl
index 3ea34de..bb94d73 100644
--- a/src/apply/ref.xsl
+++ b/src/apply/ref.xsl
@@ -104,19 +104,24 @@
 <!--
   Retrieve the QName of the target dynamic function
 
-  Usually, this would match precisely the QName of the target
+  Usually, this will match precisely the QName of the target
   function.
 
+  @var{fnreF} must be a valid dynamic function reference.
+
   @i{Implementation details:} This actually represents the QName of
   the @emph{application template}, which could differ from the target
   function name.  One reason this may be the case is to provide a
   function alias.
 -->
 <function name="f:QName" as="xs:QName?">
-  <param name="fnref" as="element( f:ref )" />
+  <param name="fnref" as="item()+" />
+
+  <variable name="desc" as="element( f:ref )"
+            select="$fnref[ 1 ]" />
 
   <variable name="target" as="element()?"
-            select="$fnref/element()[ 1 ]" />
+            select="$desc/element()[ 1 ]" />
 
   <sequence select="node-name( $target )" />
 </function>
@@ -143,4 +148,58 @@
   <sequence select="$arity" />
 </function>
 
+
+<!--
+  Retrieve a sequence of the partially applied arguments of
+  @var{fnref}
+
+  The resulting sequence may be empty.  @var{fnref} is assumed to be a
+  valid dynamic function reference; you should verify that assumption
+  beforehand.
+-->
+<function name="f:args" as="item()*">
+  <param name="fnref" as="item()+" />
+
+  <sequence select="remove( $fnref, 1 )" />
+</function>
+
+
+<!--
+  Set partially applied arguments of @var{fnref} to @var{args},
+  replacing any existing arguments
+
+  The arity of @var{fnref} will be adjusted relative to the number of
+  items in @var{args} such that the resulting dynamic function
+  reference has the illusion of being its own, new function:
+  increasing the argument count of @var{fnref} will @emph{decrease}
+  the arity of the resulting reference and vice versa.
+
+  @var{fnref} must be a valid dynamic function reference.
+-->
+<function name="f:set-args" as="item()+">
+  <param name="fnref" as="item()+" />
+  <param name="args"  as="item()*" />
+
+  <variable name="desc" as="element( f:ref )"
+            select="$fnref[ 1 ]" />
+
+  <!-- this reference may be partially applied; see below arity
+       adjustment -->
+  <variable name="target-arity" as="xs:double"
+            select="$desc/@arity + count( f:args( $fnref ) )" />
+
+  <f:ref>
+    <sequence select="$desc/@*" />
+
+    <!-- treat partial applications as their own functions (with their
+         own arities) -->
+    <attribute name="arity"
+               select="$target-arity - count( $args )" />
+
+    <sequence select="$desc/*" />
+  </f:ref>
+
+  <sequence select="$args" />
+</function>
+
 </stylesheet>
diff --git a/test/apply/ref.xspec b/test/apply/ref.xspec
index da2a9df..c3e67b1 100644
--- a/test/apply/ref.xspec
+++ b/test/apply/ref.xspec
@@ -38,6 +38,14 @@
             select="f:make-ref( QName( $foo-uri, 'foo:bar' ),
                                 $test-arity )" />
 
+  <variable name="args">
+    <foo:args>
+      <foo:a />
+      <foo:b />
+      <foo:c />
+    </foo:args>
+  </variable>
+
 
   <scenario label="f:make-ref constructor">
     <scenario label="when called with a function QName and arity">
@@ -169,10 +177,11 @@
 
 
   <scenario label="f:QName accessor">
-    <scenario label="given a valid dynamic function reference">
-      <variable name="foo-qname"
-                select="QName( $foo-uri, 'foo' )" />
+    <variable name="foo-qname"
+              select="QName( $foo-uri, 'foo' )" />
 
+    <scenario label="given a valid dynamic function reference with no
+                     argments">
       <call function="f:QName">
         <param name="fnref"
                select="f:make-ref( $foo-qname, 0 )" />
@@ -186,6 +195,22 @@
     </scenario>
 
 
+    <scenario label="given a valid dynamic function reference with
+                     argments">
+      <call function="f:QName">
+        <param name="fnref"
+               select="f:set-args( f:make-ref( $foo-qname, 0 ),
+                                   (1, 2) )" />
+      </call>
+
+      <expect label="returns QName"
+              test="$x:result instance of xs:QName" />
+
+      <expect label="returns QName of target dynamic function"
+              select="$foo-qname" />
+    </scenario>
+
+
     <scenario label="given a dynamic function reference with no target
                      node">
       <call function="f:QName">
@@ -241,4 +266,134 @@
               select="$test-arity - 3" />
     </scenario>
   </scenario>
+
+
+  <scenario label="f:set-args setter">
+    <scenario label="setting empty args on reference with no args">
+      <call function="f:set-args">
+        <param name="fnref" select="$test-fn" />
+        <param name="args"  select="()" />
+      </call>
+
+      <expect label="retains target QName"
+              test="f:QName( $x:result ) = f:QName( $test-fn )" />
+
+      <expect label="retains target arity"
+              test="f:arity( $x:result ) = f:arity( $test-fn )" />
+    </scenario>
+
+
+    <scenario label="setting args on reference with no args">
+      <call function="f:set-args">
+        <param name="fnref" select="$test-fn" />
+        <param name="args"  select="(1, 2)" />
+      </call>
+
+      <expect label="retains target QName"
+              test="f:QName( $x:result ) = f:QName( $test-fn )" />
+
+      <!-- the function is now partially applied -->
+      <expect label="reduces arity by number of arguments"
+              test="f:arity( $x:result ) = f:arity( $test-fn ) - 2" />
+    </scenario>
+
+
+    <scenario label="clearing args on reference with args">
+      <call function="f:set-args">
+        <param name="fnref"
+               select="f:set-args( $test-fn, (1, 2) )" />
+        <param name="args"
+               select="()" />
+      </call>
+
+      <expect label="retains target QName"
+              test="f:QName( $x:result ) = f:QName( $test-fn )" />
+
+      <!-- the function is no longer partially applied -->
+      <expect label="restores target function arity"
+              test="f:arity( $x:result ) = f:arity( $test-fn )" />
+    </scenario>
+
+
+    <scenario label="increasing reference argument count">
+      <call function="f:set-args">
+        <param name="fnref"
+               select="f:set-args( $test-fn, (1, 2) )" />
+        <param name="args"
+               select="(1, 2, 3)" />
+      </call>
+
+      <expect label="retains target QName"
+              test="f:QName( $x:result ) = f:QName( $test-fn )" />
+
+      <!-- the function is no longer partially applied -->
+      <expect label="reduces arity by number of argments"
+              test="f:arity( $x:result ) = f:arity( $test-fn ) - 3" />
+    </scenario>
+
+
+    <scenario label="decrasing reference argument count">
+      <call function="f:set-args">
+        <param name="fnref"
+               select="f:set-args( $test-fn, (1, 2) )" />
+        <param name="args"
+               select="1" />
+      </call>
+
+      <expect label="retains target QName"
+              test="f:QName( $x:result ) = f:QName( $test-fn )" />
+
+      <!-- the function is no longer partially applied -->
+      <expect label="increases arity by difference in argument count"
+              test="f:arity( $x:result ) = f:arity( $test-fn ) - 1" />
+    </scenario>
+  </scenario>
+
+
+  <scenario label="f:args accessor">
+    <scenario label="given a new dynamic function reference">
+      <call function="f:args">
+        <param name="fnref" select="$test-fn" />
+      </call>
+
+      <expect label="produces empty argument list"
+              select="()" />
+    </scenario>
+
+
+    <scenario label="after an initial f:set-args">
+      <call function="f:args">
+        <param name="fnref"
+               select="f:set-args( $test-fn, ($args/foo:a,
+                                              $args/foo:b) )" />
+      </call>
+
+      <expect label="returns sequence of arguments by reference"
+              test="$x:result[ 1 ] is $args/foo:a
+                      and $x:result[ 2 ] is $args/foo:b" />
+
+      <expect label="returns no other items"
+              test="count( $x:result ) = 2" />
+    </scenario>
+
+
+    <scenario label="after a f:set-args on an existing argument list">
+      <call function="f:args">
+        <param name="fnref"
+               select="f:set-args(
+                         f:set-args( $test-fn, ($args/foo:a,
+                                                $args/foo:b) ),
+                         ($args/foo:b,
+                          $args/foo:c) )" />
+      </call>
+
+      <expect label="returns sequence of arguments by reference,
+                     discarding previously set arguments"
+              test="$x:result[ 1 ] is $args/foo:b
+                      and $x:result[ 2 ] is $args/foo:c" />
+
+      <expect label="returns no other items"
+              test="count( $x:result ) = 2" />
+    </scenario>
+  </scenario>
 </description>