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diff --git a/libparc/parc/security/parc_SecureRandom.h b/libparc/parc/security/parc_SecureRandom.h
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+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+/**
+ * @file parc_SecureRandom.h
+ * @brief A cryptographically secure pseudorandom number generator that reads
+ * from a secure randomness source on the system, e.g., /dev/urandom.
+ *
+ */
+#ifndef Libparc_parc_SecureRandom
+#define Libparc_parc_SecureRandom
+
+#include <stdbool.h>
+
+#include <parc/algol/parc_Object.h>
+
+struct parc_securerandom;
+typedef struct parc_securerandom PARCSecureRandom;
+
+/**
+ * Increase the number of references to a `PARCSecureRandom` instance.
+ *
+ * Note that new `PARCSecureRandom` is not created,
+ * only that the given `PARCSecureRandom` reference count is incremented.
+ * Discard the reference by invoking `parcSecureRandom_Release`.
+ *
+ * @param [in] instance A pointer to a valid PARCSecureRandom instance.
+ *
+ * @return The same value as @p instance.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCSecureRandom *a = parcSecureRandom_Create();
+ *
+ *     PARCSecureRandom *b = parcSecureRandom_Acquire();
+ *
+ *     parcSecureRandom_Release(&a);
+ *     parcSecureRandom_Release(&b);
+ * }
+ * @endcode
+ */
+PARCSecureRandom *parcSecureRandom_Acquire(const PARCSecureRandom *instance);
+
+/**
+ * Create an instance of PARCSecureRandom
+ *
+ * @return non-NULL A pointer to a valid PARCSecureRandom instance.
+ * @return NULL An error occurred.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCSecureRandom *rng = parcSecureRandom_Create();
+ *
+ *     parcSecureRandom_Release(&rng);
+ * }
+ * @endcode
+ */
+PARCSecureRandom *parcSecureRandom_Create(void);
+
+/**
+ * Create an instance of PARCSecureRandom with a specific seed stored in
+ * a `PARCBuffer` instance.
+ *
+ * @param [in] seed A `PARCBuffer` instance.
+ *
+ * @return non-NULL A pointer to a valid PARCSecureRandom instance.
+ * @return NULL An error occurred.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCBuffer *seed = ...
+ *     PARCSecureRandom *rng = parcSecureRandom_CreateWithSeed(seed);
+ *
+ *     parcSecureRandom_Release(&rng);
+ * }
+ * @endcode
+ */
+PARCSecureRandom *parcSecureRandom_CreateWithSeed(PARCBuffer *seed);
+
+/**
+ * Generate a 32-bit unsigned integer from a `PARCSecureRandom` instance.
+ *
+ * @param [in] rng A `PARCSecureRandom` instance.
+ *
+ * @return non-NULL A pointer to a valid PARCSecureRandom instance.
+ * @return NULL An error occurred.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCSecureRandom *rng = parcSecureRandom_Create();
+ *
+ *     uint32_t nextWord = parcSecureRandom_Next(rng);
+ *     // use the word
+ * }
+ * @endcode
+ */
+uint32_t parcSecureRandom_Next(PARCSecureRandom *rng);
+
+/**
+ * Fill a `PARCBuffer` instance with random bytes from a `PARCSecureRandom` instance.
+ * The resultant `PARCBuffer` will be ready for reading, i.e., one does not need
+ * to call `parcBuffer_Flip()` on the result.
+ *
+ * @param [in] rng A `PARCSecureRandom` instance.
+ * @param [in] buffer A `PARCBuffer` instance to fill.
+ *
+ * @return non-NULL A pointer to a valid PARCSecureRandom instance.
+ * @return NULL An error occurred.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCSecureRandom *rng = parcSecureRandom_Create();
+ *
+ *     PARCBuffer *buffer = parcBuffer_Allocate(32);
+ *     ssize_t numBytes = parcSecureRandom_NextBytes(rng, buffer);
+ *     // use the buffer
+ * }
+ * @endcode
+ */
+ssize_t parcSecureRandom_NextBytes(PARCSecureRandom *rng, PARCBuffer *buffer);
+
+/**
+ * Determine if an instance of `PARCSecureRandom` is valid.
+ *
+ * Valid means the internal state of the type is consistent with its required current or future behaviour.
+ * This may include the validation of internal instances of types.
+ *
+ * @param [in] instance A pointer to a valid PARCSecureRandom instance.
+ *
+ * @return true The instance is valid.
+ * @return false The instance is not valid.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCSecureRandom *rng = parcSecureRandom_Create();
+ *
+ *     if (parcSecureRandom_IsValid(rng)) {
+ *         printf("Instance is valid.\n");
+ *     }
+ *
+ *     parcSecureRandom_Release(&rng);
+ * }
+ * @endcode
+ *
+ */
+bool parcSecureRandom_IsValid(const PARCSecureRandom *instance);
+
+/**
+ * Release a previously acquired reference to the given `PARCSecureRandom` instance,
+ * decrementing the reference count for the instance.
+ *
+ * The pointer to the instance is set to NULL as a side-effect of this function.
+ *
+ * If the invocation causes the last reference to the instance to be released,
+ * the instance is deallocated and the instance's implementation will perform
+ * additional cleanup and release other privately held references.
+ *
+ * @param [in,out] instancePtr A pointer to a pointer to the instance to release.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCSecureRandom *rng = parcSecureRandom_Create();
+ *
+ *     parcSecureRandom_Release(&rng);
+ * }
+ * @endcode
+ */
+void parcSecureRandom_Release(PARCSecureRandom **instancePtr);
+#endif