diff --git a/Headers/gnustep/base/Invocation.h b/Headers/gnustep/base/Invocation.h
new file mode 100644
index 000000000..708e9f583
--- /dev/null
+++ b/Headers/gnustep/base/Invocation.h
@@ -0,0 +1,82 @@
+#ifndef __Invocation_h_OBJECTS_INCLUDE
+#define __Invocation_h_OBJECTS_INCLUDE
+
+/* 
+   Use these for notifications!
+   Don't forget to make these archivable / transportable.
+   WARNING: All the (char*) type arguments and return values may
+   extraneous stuff after the first type.
+*/
+
+#include <objects/stdobjects.h>
+#include <objects/Collection.h>
+
+@interface Invocation : NSObject
+{
+  char *encoding;
+  unsigned return_size;
+  void *return_value;
+}
+- initWithReturnType: (const char *)encoding;
+- (void) invoke;
+- (void) invokeWithObject: anObj;
+- (void) invokeWithElement: (elt)anElt;
+- (const char *) returnType;
+- (unsigned) returnSize;
+- (void) getReturnValue: (void *)addr;
+@end
+
+@interface ArgframeInvocation : Invocation
+{
+  arglist_t argframe;
+  /* char *function_encoding; Using return_encoding */
+}
+- initWithArgframe: (arglist_t)frame type: (const char *)e;
+- initWithType: (const char *)e;
+- (const char *) argumentTypeAtIndex: (unsigned)i;
+- (unsigned) argumentSizeAtIndex: (unsigned)i;
+- (void) getArgument: (void*)addr atIndex: (unsigned)i;
+- (void) setArgumentAtIndex: (unsigned)i 
+    toValueAt: (const void*)addr;
+@end
+
+@interface MethodInvocation : ArgframeInvocation
+- initWithArgframe: (arglist_t)frame selector: (SEL)s;
+- initWithSelector: (SEL)s;
+- (void) invokeWithTarget: t;
+- (SEL) selector;
+- (void) setSelector: (SEL)s;
+- target;
+- (void) setTarget: t;
+@end
+
+@interface FunctionInvocation : ArgframeInvocation
+{
+  void (*function)();
+}
+- initWithFunction: (void(*)())f
+    argframe: (arglist_t)frame type: (const char *)e;
+- initWithFunction: (void(*)())f;
+@end
+
+#if 0
+// NO, instead do above;
+@interface EltFunctionInvocation
+{
+  void (*func)(elt);
+}
+- initWithEltFunction: (void(*)(elt))func;
+@end
+
+@interface TclInvocation
+- initWithTcl: (Tcl*)t command: (const char*)c;
+@end
+
+@interface Collection (Invokes)
+- makeObjectsInvoke: (MethodInvocation*)i;
+- withObjectsInvoke: (Invocation*)i;
+- withElementsInvoke: (EltInvocation*)i;
+@end
+#endif
+
+#endif /* __Invocation_h_OBJECTS_INCLUDE */
diff --git a/Source/Invocation.m b/Source/Invocation.m
new file mode 100644
index 000000000..1c8f87a41
--- /dev/null
+++ b/Source/Invocation.m
@@ -0,0 +1,285 @@
+
+#include <objects/Invocation.h>
+
+/* Deal with strrchr: */
+#if STDC_HEADERS || HAVE_STRING_H
+#include <string.h>
+/* An ANSI string.h and pre-ANSI memory.h might conflict.  */
+#if !STDC_HEADERS && HAVE_MEMORY_H
+#include <memory.h>
+#endif /* not STDC_HEADERS and HAVE_MEMORY_H */
+#define rindex strrchr
+#define bcopy(s, d, n) memcpy ((d), (s), (n))
+#define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
+#define bzero(s, n) memset ((s), 0, (n))
+#else /* not STDC_HEADERS and not HAVE_STRING_H */
+#include <strings.h>
+/* memory.h and strings.h conflict on some systems.  */
+#endif /* not STDC_HEADERS and not HAVE_STRING_H */
+
+
+/* 
+   Put something like this in Collecting:
+   - withObjectsAtArgumentIndex: (unsigned)index
+       invoke: (Invocation*)invocation;
+   - putObjectsAtArgumentIndex: (unsigned)index
+       andInvoke: (Invocation*)invocation;
+   - invoke: (Invocation*)invocation
+       withObjectsAtArgumentIndex: (unsigned)index
+*/
+
+@implementation Invocation
+
+- initWithReturnType: (const char *)enc
+{
+  int l = strlen(enc);
+  OBJC_MALLOC(encoding, char, l);
+  memcpy(encoding, enc, l);
+  return_size = objc_sizeof_type(encoding);
+  return_value = NULL;
+  return self;
+}
+- (void) invoke
+{
+  [self subclassResponsibility:_cmd];
+}
+
+- (void) invokeWithObject: anObj
+{
+  [self invoke];
+}
+
+- (void) invokeWithElement: (elt)anElt
+{
+  [self invoke];
+}
+
+- (const char *) returnType
+{
+  return encoding;
+}
+
+- (unsigned) returnSize
+{
+  return return_size;
+}
+
+- (void) getReturnValue: (void *)addr
+{
+  memcpy(addr, return_value, return_size);
+}
+
+- (void) dealloc
+{
+  OBJC_FREE(encoding);
+  [super dealloc];
+}
+
+@end
+
+
+static int
+types_get_size_of_stack_arguments(const char *types)
+{
+  const char* type = objc_skip_typespec (types);
+  return atoi(type);
+}
+
+static int
+types_get_size_of_register_arguments(const char *types)
+{
+  const char* type = strrchr(types, '+');
+  if (type)
+    return atoi(++type) + sizeof(void*);
+  else
+    return 0;
+}
+
+/* To fix temporary bug in method_get_next_argument() on m68k */
+static char*
+my_method_get_next_argument (arglist_t argframe,
+			          const char **type)
+{
+  const char *t = objc_skip_argspec (*type);
+
+  if (*t == '\0')
+    return 0;
+
+  *type = t;
+  t = objc_skip_typespec (t);
+
+  if (*t == '+')
+    return argframe->arg_regs + atoi(++t);
+  else
+    /* xxx What's going on here?  This -8 needed on my 68k NeXT box. */
+#if m68k
+    return argframe->arg_ptr + (atoi(t) - 8);
+#else
+    return argframe->arg_ptr + atoi(t);
+#endif
+}
+
+@implementation ArgframeInvocation
+
+/* This is the designated initializer. */
+- initWithArgframe: (arglist_t)frame type: (const char *)type
+{
+  int stack_argsize, reg_argsize;
+
+  /* xxx we could just use the return part.  Does this matter? */
+  [super initWithReturnType:type];
+
+  /* allocate the argframe */
+  stack_argsize = types_get_size_of_stack_arguments(type);
+  reg_argsize = types_get_size_of_register_arguments(type);
+  argframe = (arglist_t) (*objc_malloc)(sizeof(char*) + reg_argsize);
+  if (stack_argsize)
+    argframe->arg_ptr = (*objc_malloc)(stack_argsize);
+  else
+    argframe->arg_ptr = 0;
+
+  /* copy the frame into the argframe */
+  if (frame)
+    {
+      memcpy((char*)argframe + sizeof(char*), 
+	     (char*)frame + sizeof(char*),
+	     reg_argsize);
+      memcpy(argframe->arg_ptr, frame->arg_ptr, stack_argsize);
+    }
+
+  return self;
+}
+
+- initWithType: (const char *)e
+{
+  [self initWithArgframe:NULL type:e];
+  return self;
+}
+
+- (const char *) argumentTypeAtIndex: (unsigned)i
+{
+  const char *tmptype = encoding;
+
+  do 
+    {
+      tmptype = objc_skip_argspec(objc_skip_typespec(tmptype));
+    }
+  while (i--);
+  return tmptype;
+}
+
+- (unsigned) argumentSizeAtIndex: (unsigned)i
+{
+  return objc_sizeof_type([self argumentTypeAtIndex:i]);
+}
+
+- (void) getArgument: (void*)addr atIndex: (unsigned)i
+{
+  const char *tmptype = encoding;
+  void *datum;
+
+  do
+    datum = my_method_get_next_argument(argframe, &tmptype);
+  while (i--);
+  memcpy(addr, datum, objc_sizeof_type(tmptype));
+}
+
+- (void) setArgumentAtIndex: (unsigned)i 
+    toValueAt: (const void*)addr
+{
+  const char *tmptype = encoding;
+  void *datum;
+
+  do
+    datum = my_method_get_next_argument(argframe, &tmptype);
+  while (i--);
+  memcpy(datum, addr, objc_sizeof_type(tmptype));
+}
+
+@end
+
+
+@implementation MethodInvocation
+
+- initWithArgframe: (arglist_t)frame selector: (SEL)sel
+{
+  [self initWithArgframe:frame type:sel_get_type(sel)];
+  return self;
+}
+
+- initWithSelector: (SEL)s
+{
+  [self initWithArgframe:NULL selector:s];
+  return self;
+}
+
+- (void) invoke
+{
+  void *ret;
+  IMP imp;
+
+  imp = get_imp([self target], [self selector]);
+  assert(imp);
+  ret = __builtin_apply((void(*)(void))imp,
+			argframe, 
+			type_get_size_of_stack_arguments(encoding));
+  if (*encoding == 'd')
+    memcpy(return_value, (char*)ret + 2*sizeof(void*), return_size);
+  else
+    memcpy(return_value, ret, return_size);
+}
+
+- (void) invokeWithTarget: t
+{
+  [self setArgumentAtIndex:0 toValueAt:&t];
+  [self invoke];
+}
+
+- (SEL) selector
+{
+  SEL s;
+  [self getArgument:&s atIndex:1];
+  return s;
+}
+
+- (void) setSelector: (SEL)s
+{
+  [self setArgumentAtIndex:1 toValueAt:&s];
+  if (sel_types_match(sel_get_type([self selector]), sel_get_type(s)))
+    [self setArgumentAtIndex:1 toValueAt:&s];
+  else
+    {
+      [self notImplemented:_cmd];
+      /* We will need to reallocate the argframe */
+    }
+}
+
+- target
+{
+  id t;
+  [self getArgument:&t atIndex:1];
+  return t;
+}
+
+- (void) setTarget: t
+{
+  [self setArgumentAtIndex:0 toValueAt:&t];
+}
+
+@end
+
+
+/* Many other kinds of Invocations are possible:
+   SchemeInvocation, TclInvocation */
+
+#if 0
+What is this nonsense?
+@interface StreamInvocation
+@interface LogInvocation
+@interface PrintingInvocation
+{
+  Stream *stream;
+  char *format_string;
+}
+@end
+#endif
diff --git a/Source/objects/Invocation.h b/Source/objects/Invocation.h
new file mode 100644
index 000000000..708e9f583
--- /dev/null
+++ b/Source/objects/Invocation.h
@@ -0,0 +1,82 @@
+#ifndef __Invocation_h_OBJECTS_INCLUDE
+#define __Invocation_h_OBJECTS_INCLUDE
+
+/* 
+   Use these for notifications!
+   Don't forget to make these archivable / transportable.
+   WARNING: All the (char*) type arguments and return values may
+   extraneous stuff after the first type.
+*/
+
+#include <objects/stdobjects.h>
+#include <objects/Collection.h>
+
+@interface Invocation : NSObject
+{
+  char *encoding;
+  unsigned return_size;
+  void *return_value;
+}
+- initWithReturnType: (const char *)encoding;
+- (void) invoke;
+- (void) invokeWithObject: anObj;
+- (void) invokeWithElement: (elt)anElt;
+- (const char *) returnType;
+- (unsigned) returnSize;
+- (void) getReturnValue: (void *)addr;
+@end
+
+@interface ArgframeInvocation : Invocation
+{
+  arglist_t argframe;
+  /* char *function_encoding; Using return_encoding */
+}
+- initWithArgframe: (arglist_t)frame type: (const char *)e;
+- initWithType: (const char *)e;
+- (const char *) argumentTypeAtIndex: (unsigned)i;
+- (unsigned) argumentSizeAtIndex: (unsigned)i;
+- (void) getArgument: (void*)addr atIndex: (unsigned)i;
+- (void) setArgumentAtIndex: (unsigned)i 
+    toValueAt: (const void*)addr;
+@end
+
+@interface MethodInvocation : ArgframeInvocation
+- initWithArgframe: (arglist_t)frame selector: (SEL)s;
+- initWithSelector: (SEL)s;
+- (void) invokeWithTarget: t;
+- (SEL) selector;
+- (void) setSelector: (SEL)s;
+- target;
+- (void) setTarget: t;
+@end
+
+@interface FunctionInvocation : ArgframeInvocation
+{
+  void (*function)();
+}
+- initWithFunction: (void(*)())f
+    argframe: (arglist_t)frame type: (const char *)e;
+- initWithFunction: (void(*)())f;
+@end
+
+#if 0
+// NO, instead do above;
+@interface EltFunctionInvocation
+{
+  void (*func)(elt);
+}
+- initWithEltFunction: (void(*)(elt))func;
+@end
+
+@interface TclInvocation
+- initWithTcl: (Tcl*)t command: (const char*)c;
+@end
+
+@interface Collection (Invokes)
+- makeObjectsInvoke: (MethodInvocation*)i;
+- withObjectsInvoke: (Invocation*)i;
+- withElementsInvoke: (EltInvocation*)i;
+@end
+#endif
+
+#endif /* __Invocation_h_OBJECTS_INCLUDE */