diff --git a/Cantera/clib/src/ct.cpp b/Cantera/clib/src/ct.cpp
index 0ccdc083e..ec1617df6 100755
--- a/Cantera/clib/src/ct.cpp
+++ b/Cantera/clib/src/ct.cpp
@@ -504,7 +504,10 @@ extern "C" {
                 }
             }
             Kinetics* kin = newKineticsMgr(*x, phases);
-            return Storage::storage()->addKinetics(kin);
+            if (kin)
+                return Storage::storage()->addKinetics(kin);
+            else
+                return 0;
         }
         catch (CanteraError) { return -1; }
     }
diff --git a/Cantera/clib/src/ctxml.cpp b/Cantera/clib/src/ctxml.cpp
index cf9a896b6..c144ed01b 100644
--- a/Cantera/clib/src/ctxml.cpp
+++ b/Cantera/clib/src/ctxml.cpp
@@ -1,6 +1,7 @@
 
 // Cantera includes
 #include "ctml.h"
+#include "importCTML.h"
 
 #include "Cabinet.h"
 #include "Storage.h"
@@ -28,8 +29,10 @@ extern "C" {
 
     int DLL_EXPORT xml_new(const char* name = 0) {
         XML_Node* x;
-        if (!name) x = new XML_Node;
-        else x = new XML_Node(string(name));
+        if (!name) 
+            x = new XML_Node;
+        else 
+            x = new XML_Node(string(name));
         return Cabinet<XML_Node>::cabinet()->add(x);
     }
 
@@ -66,6 +69,14 @@ extern "C" {
         catch (CanteraError) { return -1; }
     }
 
+    int DLL_EXPORT xml_preprocess_and_build(int i, const char* file) {
+        try {
+            get_CTML_Tree(_xml(i), string(file));
+            return 0;
+        }
+        catch (CanteraError) { return -1; }
+    }
+
     int DLL_EXPORT xml_attrib(int i, const char* key, char* value) {
         try {
             string ky = string(key);
diff --git a/Cantera/clib/src/ctxml.h b/Cantera/clib/src/ctxml.h
index a6aaf2f97..3abe553db 100644
--- a/Cantera/clib/src/ctxml.h
+++ b/Cantera/clib/src/ctxml.h
@@ -10,6 +10,7 @@ extern "C" {
     int DLL_IMPORT xml_copy(int i);
     int DLL_IMPORT xml_assign(int i, int j);
     int DLL_IMPORT xml_build(int i, const char* file);
+    int DLL_IMPORT xml_preprocess_and_build(int i, const char* file);
     int DLL_IMPORT xml_attrib(int i, const char* key, char* value);
     int DLL_IMPORT xml_addAttrib(int i, const char* key, const char* value);
     int DLL_IMPORT xml_addComment(int i, const char* comment);
diff --git a/Cantera/matlab/cantera/@Solution/Solution.m b/Cantera/matlab/cantera/@Solution/Solution.m
index 95feb8885..da74776ec 100755
--- a/Cantera/matlab/cantera/@Solution/Solution.m
+++ b/Cantera/matlab/cantera/@Solution/Solution.m
@@ -41,7 +41,8 @@ if isa(x,'Solution')
 elseif isa(x,'XML_Node')
   xp = x;
 else
-  doc = XML_Node('doc', x);
+  doc = XML_Node('doc');
+  build(doc, x, 1);
   xp = child(doc,'ctml/phase');
 end
 t = ThermoPhase(xp);
diff --git a/Cantera/matlab/cantera/@XML_Node/build.m b/Cantera/matlab/cantera/@XML_Node/build.m
index a7c46d51f..3f8746ae5 100644
--- a/Cantera/matlab/cantera/@XML_Node/build.m
+++ b/Cantera/matlab/cantera/@XML_Node/build.m
@@ -1,9 +1,13 @@
-function x = build(x, file)
+function x = build(x, file, pre)
 
-if nargin ~= 2 | ~isa(file,'char')
+if nargin < 2 | ~isa(file,'char')
   error('Syntax error. Type "help build" for more information.')
 end
 
-iok = ctmethods(10, 4, x.id, file);
+if nargin == 2
+  iok = ctmethods(10, 4, x.id, file);
+else
+  iok = ctmethods(10, 15, x.id, file);
+end
 
 
diff --git a/Cantera/matlab/cantera/private/xmlmethods.cpp b/Cantera/matlab/cantera/private/xmlmethods.cpp
index a4c1b46ca..0b90542a0 100644
--- a/Cantera/matlab/cantera/private/xmlmethods.cpp
+++ b/Cantera/matlab/cantera/private/xmlmethods.cpp
@@ -103,7 +103,10 @@ void xmlmethods( int nlhs, mxArray *plhs[],
                 j = getInt(prhs[3]);
                 iok = xml_removeChild(i, j);
                 break;
-
+        case 15:
+            file = getString(prhs[3]);
+            iok = xml_preprocess_and_build(i, file);
+            break;
             default:
                 mexErrMsgTxt("unknown job parameter");
             }
diff --git a/Cantera/python/Cantera/Interface.py b/Cantera/python/Cantera/Interface.py
index 295c4e6a5..795f96ce8 100644
--- a/Cantera/python/Cantera/Interface.py
+++ b/Cantera/python/Cantera/Interface.py
@@ -20,18 +20,25 @@ class Interface(SurfacePhase, Kinetics):
         self._owner = 0
         self.verbose = 1
 
-        fn = string.split(src,'#')
-        fn = fn[0]
+        fn = src.split('#')
         id = ""
-        if len(fn) > 1: id = fn[1]        
+        if len(fn) > 1:
+            id = fn[1]        
+            fn = fn[0]
         fname = os.path.basename(fn)
         ff = os.path.splitext(fname)
         
         # get the 'phase' element
+
+        if src and not root:
+            root = XML.XML_Node(name = 'doc', src = fn, preprocess = 1)
+            
         if id:
-            s = XML.find_XML(src=src, root=root, id=id)
+            s = root.child(id = id)            
+            #s = XML.find_XML(src=src, root=root, id=id)
         else:
-            s = XML.find_XML(src=src, root=root, name="phase")                
+            s = root.child(name = "phase")            
+            #s = XML.find_XML(src=src, root=root, name="phase")                
 
         # get the equation of state model
         SurfacePhase.__init__(self, xml_phase=s)
diff --git a/Cantera/python/Cantera/XML.py b/Cantera/python/Cantera/XML.py
index 20b9772c7..c55fe8928 100644
--- a/Cantera/python/Cantera/XML.py
+++ b/Cantera/python/Cantera/XML.py
@@ -10,7 +10,7 @@ import exceptions
     
 class XML_Node:
     """A node in an XML tree."""
-    def __init__(self, name="--", src="", wrap=0, root=None):
+    def __init__(self, name="--", src="", wrap=0, root=None, preprocess=0):
         """
         Return an instance representing a node in an XML tree.
         If 'src' is specified, then the XML tree found in file 'src' is
@@ -25,7 +25,7 @@ class XML_Node:
         else:
             self._xml_id = _cantera.xml_new(name)
             if src:
-                _cantera.xml_build(self._xml_id, src)
+                _cantera.xml_build(self._xml_id, src, preprocess)
             self._root = self
         
     def __del__(self):
diff --git a/Cantera/python/Cantera/ctml_writer.py b/Cantera/python/Cantera/ctml_writer.py
index 073795120..8a80ddac3 100644
--- a/Cantera/python/Cantera/ctml_writer.py
+++ b/Cantera/python/Cantera/ctml_writer.py
@@ -187,7 +187,7 @@ class species(writer):
     
     def __init__(self,
                  name = 'missing name!',
-                 atoms = 'missing atoms!',
+                 atoms = '',
                  comment = '',
                  thermo = None,
                  transport = None,
@@ -293,7 +293,7 @@ class const_cp(thermo):
     """Constant specific heat."""
     
     def __init__(self, tmax = -1.0, tmin = -1.0,
-                 t0 = 0.0, cp0 = 0.0, h0 = 0.0, s0 = 0.0):
+                 t0 = 298.15, cp0 = 0.0, h0 = 0.0, s0 = 0.0):
         self._t = [tmin, tmax]
         self._c = [t0, h0, s0, cp0]
         
@@ -364,22 +364,14 @@ class sticking_prob(writer):
         self._sp = species
         
     def build(self, p):
-        ig = ideal_gas()
-        for ph in _phases:
-            if ph.has_species(self._sp):
-                if ph._eos.__class__ == ig.__class__:
-                    pass
-                else:
-                    raise ('sticking probabilities only implemented for '
-                           +'species in ideal gas mixtures')
-                
         a = p.addChild('Stick')
+        a['species'] = self._sp
         addFloat(a,'A',self._c[0],fmt = '%14.6E')
         a.addChild('n',`self._c[1]`)
-        if type(self._c[2]) == types.FloatType:
-            addFloat(a,'E',(self._c[2],_ue))
+        if isnum(self._c[2]):
+            addFloat(a,'E',(self._c[2],_ue), fmt = '%f')
         else:
-            addFloat(a,'E',self._c[2])                
+            addFloat(a,'E',self._c[2], fmt = '%f')                
 
         
 class reaction(writer):
@@ -404,6 +396,7 @@ class reaction(writer):
         self._r = getReactionSpecies(r)
         self._p = getReactionSpecies(p)
         self._kf = kf
+        self._igspecies = []
         self._type = ''
         _reactions.append(self)
 
@@ -420,7 +413,7 @@ class reaction(writer):
                 nstr = '0'+`self._num`                
             else:
                 nstr = `self._num`
-            id = 'reaction_'+nstr
+            id = nstr
         p.addComment("   reaction "+id+"    ")                
         r = p.addChild('reaction')
         r['id'] = id
@@ -447,6 +440,8 @@ class reaction(writer):
             for ph in _phases:
                 if ph.has_species(s):
                     nm, nl = ph.conc_dim()
+                    if ph.is_ideal_gas():
+                        self._igspecies.append(s)
                     break
             if nm < 0:
                 print self._r
@@ -477,6 +472,8 @@ class reaction(writer):
         kfnode = r.addChild('rateCoeff')
         if self._type == '':
             self._kf = [self._kf]
+        elif self._type == 'surface':
+            self._kf = [self._kf]            
         elif self._type == 'threeBody':
             self._kf = [self._kf]
             mdim += 1
@@ -602,6 +599,15 @@ class falloff_reaction(reaction):
             self._falloff.build(kfnode)
 
 
+class surface_reaction(reaction):
+
+    def __init__(self,
+                 equation = '',
+                 kf = None,
+                 id = ''):
+        reaction.__init__(self, equation, kf, id)
+        self._type = 'surface'
+
 #--------------            
 
 
@@ -609,15 +615,15 @@ class state:
     def __init__(self,
                  temperature = None,
                  pressure = None,
-                 moleFractions = None,
-                 massFractions = None,
+                 mole_fractions = None,
+                 mass_fractions = None,
                  density = None,
                  coverages = None):
         self._t = temperature
         self._p = pressure
         self._rho = density
-        self._x = moleFractions
-        self._y = massFractions
+        self._x = mole_fractions
+        self._y = mass_fractions
         self._c = coverages
         
     def build(self, ph):
@@ -627,7 +633,7 @@ class state:
         if self._rho: addFloat(st, 'density', self._rho)
         if self._x: st.addChild('moleFractions', self._x)
         if self._y: st.addChild('massFractions', self._y)
-        if self._c: st.addChild('moleFractions', self._c)
+        if self._c: st.addChild('coverages', self._c)
     
 
 class phase(writer):
@@ -696,7 +702,9 @@ class phase(writer):
         global _phases
         _phases.append(self)
 
-
+    def is_ideal_gas(self):
+        return 0
+    
     def is_pure(self):
         return 0
     
@@ -777,7 +785,7 @@ class ideal_gas(phase):
                  species = '',
                  reactions = 'none',
                  kinetics = 'GasKinetics',
-                 transport = 'Mix',
+                 transport = 'None',
                  initial_state = None):
         
         phase.__init__(self, name, 3, elements, species, reactions,
@@ -795,10 +803,78 @@ class ideal_gas(phase):
         k['model'] = self._kin
         t = ph.addChild('transport')
         t['model'] = self._tr
+
+    def is_ideal_gas(self):
+        return 1
+    
+class pure_solid(phase):
+    """A pure solid."""
+    def __init__(self,
+                 name = '',
+                 elements = '',
+                 species = '',
+                 density = -1.0,
+                 transport = 'None',
+                 initial_state = None):
         
+        phase.__init__(self, name, 3, elements, species, 'none',
+                       initial_state)
+        self._dens = density
+        self._pure = 1
+        if self._dens < 0.0:
+            raise 'density must be specified.'        
+        self._pure = 0
+        self._tr = transport
+
+        
+    def build(self, p):
+        ph = phase.build(self, p)
+        e = ph.addChild("thermo")
+        e['model'] = 'SolidCompound'
+        addFloat(e, 'density', self._dens)
+        if self._tr:
+            t = ph.addChild('transport')
+            t['model'] = self._tr
         
 
-    
+class ideal_interface(phase):
+    """An ideal interface."""
+    def __init__(self,
+                 name = '',
+                 elements = '',
+                 species = '',
+                 reactions = 'none',
+                 site_density = 0.0,
+                 phases = [],
+                 kinetics = 'Interface',
+                 transport = 'None',
+                 initial_state = None):
+
+        self._type = 'surface'
+        phase.__init__(self, name, 2, elements, species, reactions,
+                       initial_state)
+        self._pure = 0
+        self._kin = kinetics
+        self._tr = transport
+        self._phases = phases
+        self._sitedens = site_density
+        
+    def build(self, p):
+        ph = phase.build(self, p)
+        e = ph.addChild("thermo")
+        e['model'] = 'Surface'
+        addFloat(e, 'site_density',self._sitedens)
+        k = ph.addChild("kinetics")
+        k['model'] = self._kin
+        t = ph.addChild('transport')
+        t['model'] = self._tr
+        p = ph.addChild('phaseArray',self._phases)
+
+
+    def conc_dim(self):
+        return (1, -2)
+
+        
 #------------------ equations of state --------------------------
 
 class eos(writer):
diff --git a/Cantera/python/Cantera/importFromFile.py b/Cantera/python/Cantera/importFromFile.py
index 84f14cf8f..8c7e05c89 100755
--- a/Cantera/python/Cantera/importFromFile.py
+++ b/Cantera/python/Cantera/importFromFile.py
@@ -1,9 +1,45 @@
 import solution
+import Interface
+import XML
+
+def preprocess(f):
+    fn = f.split('.')
+    prepr = 1
+    base = f
+    if len(fn) == 2:
+        base = fn[0]
+        if fn[1] == '.xml' or fn[1] == '.ctml':
+            prepr = 0
+    if prepr:
+        from Cantera import pip
+        pip.process(f)                
+        src = base+'.xml'
+    else:
+        src = f
+    return src
 
 def importPhase(file = '', name = ''):
+    return importPhases(file, [name])[0]
+
+def importPhases(file = '', names = []):
+    """Import multiple phase definitions.
+    By importing all required phases in one file with one function call,
+    the preprocessor and CTML parser only need to run once.
+    """
+    s = []
+    root = XML.XML_Node(name = 'doc', src = file, preprocess = 1)
+    for nm in names:
+        src = '#'+nm
+        s.append(solution.Solution(src, root = root))
+    return s
+
+def importInterface(file = '', name = '', phases = []):
+    #file = preprocess(file)
+    root = XML.XML_Node(name = 'doc', src = file, preprocess = 1)
     if name:
         src = file+'#'+name
     else:
         src = file
-    return solution.Solution(src)
-
+    print phases
+    return Interface.Interface(src = src, root = root, phases = phases)    
+    
diff --git a/Cantera/python/Cantera/pip.py b/Cantera/python/Cantera/pip.py
index 7628ed37f..9146a7c56 100644
--- a/Cantera/python/Cantera/pip.py
+++ b/Cantera/python/Cantera/pip.py
@@ -22,8 +22,10 @@ write()
     fo.write(txt)
     fo.close()
     cmd = sys.executable+' '+fname+' '+name+' '+base
-    os.system(cmd)
+    err = os.system(cmd)
     os.remove(fname)
+    if err:
+        sys.exit(-1)
 
 
 
diff --git a/Cantera/python/Cantera/solution.py b/Cantera/python/Cantera/solution.py
index 365e0e5c9..13c6a382b 100755
--- a/Cantera/python/Cantera/solution.py
+++ b/Cantera/python/Cantera/solution.py
@@ -37,26 +37,20 @@ class Solution(ThermoPhase, Kinetics, Transport):
         self.verbose = 1
         fn = src.split('#')
         id = ""
-        if len(fn) > 1: id = fn[1]
-        fn = fn[0]
+        if len(fn) > 1:
+            id = fn[1]
+            fn = fn[0]
             
         fname = os.path.basename(fn)
         ff = os.path.splitext(fname)
-        if ff[1] <> '.xml' and ff[1] <> '.ctml':
-            #if ff[1] == '.py' or ff[1] == '.in':
-            from Cantera import pip
-            pip.process(fname)                
-            #else:
-            #    ctmodule.ck2ctml(src, thermo_db, transport_db, ff[0]+'.xml',
-            #                     ff[0])
-            src = ff[0]+'.xml'
-        
-        # get the 'phase' element
 
+        if src and not root:
+            root = XML.XML_Node(name = 'doc', src = fn, preprocess = 1)
+            
         if id:
-            s = XML.find_XML(src=src, root=root, id=id)
+            s = root.child(id = id)
         else:
-            s = XML.find_XML(src=src, root=root, name="phase")        
+            s = root.child(name = "phase")
 
         # get the equation of state model
         ThermoPhase.__init__(self, xml_phase=s)
@@ -68,8 +62,6 @@ class Solution(ThermoPhase, Kinetics, Transport):
         Transport.__init__(self, xml_phase=s, phase=self,
                            model = transport, loglevel=4)
         
-        #self.setState_TP(300.0, OneAtm)
-
 
     def __repr__(self):
         return _cantera.phase_report(self._phase_id, self.verbose)
diff --git a/Cantera/python/src/ctxml_methods.cpp b/Cantera/python/src/ctxml_methods.cpp
index cfd2c2cec..8d8d1ae4b 100644
--- a/Cantera/python/src/ctxml_methods.cpp
+++ b/Cantera/python/src/ctxml_methods.cpp
@@ -23,11 +23,15 @@ py_xml_del(PyObject *self, PyObject *args)
 static PyObject*
 py_xml_build(PyObject *self, PyObject *args)
 {
-    int n;
+    int n, pre;
     char* file;
-    if (!PyArg_ParseTuple(args, "is:xml_build", &n, &file))
+    if (!PyArg_ParseTuple(args, "isi:xml_build", &n, &file, &pre))
         return NULL;
-    int iok = xml_build(n, file);
+    int iok;
+    if (pre > 0) 
+        iok = xml_preprocess_and_build(n, file);
+    else
+        iok = xml_build(n, file);
     if (iok < 0) return reportError(iok);
     return Py_BuildValue("i",0);
 }